
Book -■ I Y/ Is j) 

Copyright^ . 



COPYRIGHT DEPOSiTV 



AIR BRAKE TEXT 

FOR 

ENGINEERS 
and FIREMEN 



A COMPLETE TREATISE ON THE WES 

TINGHOUSE and NEW YORK AIR 

BRAKE and SIGNAL SYSTEMS 

AIR BRAKE PRACTIC and 

TRAIN HANDLING 



EDITED AND PUBLISHED 

BY 

FRED McARDLE AND HENRY HELMHOLTZ 
CHICAGO 1909. 




k^ 



\* 



LIBRARY of CONGRESS 
Two Cooies Received 

MAK 29 W9 

0LAB8 O. AAO, No. 



Copyrighted 1908, 1909 

BY 

FEED McAEDLE 






1 



j\ 



PREFACE. 

The instructions contained in the "Air Brake Text" for 
Engineers and Firemen was prepared by Locomotive 
Engineers who have had years of experience in practical 
air brake practice. The subject matter being thoroughly 
and briefly treated in plain, comprehensive language, and 
can be easily understood by all who give the text careful 
study. 

The work contains a treatise on all of the old air brake 
equipment, in addition to a complete description and treatise 
of the latest Westinghouse and New York equipments, 
which are briefly explained and cover all of the points 
necessary to qualify the engineman to pass a thorough exam- 
ination on air brake operation and train handling. 

It is unlike all other air brake text-books and catechisms 
which contain a large amount of matter pertaining to brake 
leverage, mathematical problems, calculations of braking 
power, and maintenance of brake equipment in repair yards, 
which is of no special value to enginemen in brake operation 
and has been omitted in this text, with a view of qualifying 
the engineman to become competent in air brake practice. 

A knowledge of brake leverage, braking power and 
maintenance of equipment is valuable to an engineman, but 
should not be confounded with practical air brake practice 
and train handling. 

The Authors have aimed to treat each subject in such 
a manner that they may be readily understood by the 
beginners, as well as by those who are more advanced 
in the service. 

Fred McArdle ; 
Henry Helmholtz. 
Chicago, March, 1909. 



CONTENTS. 



WESTINGHOUSE AIR BRAKE AND SIGNAL 

SYSTEM . . 1-244 

Westinghouse Air Pumps . 3 

Eight-Inch Air Pump 3 

Nine and One-Half-Inch Pump 6 

Defects of the Eight and Nine and One-Half- 
Inch Pumps 14 

Eight and One-Half-Inch Cross-Compound Air 

Compressor 20 

Main Reservoir 28 

Westinghouse Air Pump Governors 30 

Single Governor 30 

Duplex Pump Governor With Siamese Fittings. 32 

Defects of Pump Governors 36 

Duplex Air Gauge 37 

Engineer's Brake Valves 40 

D-8 Brake Valve 40 

Equalizing Reservoir 47 

G-6 Brake Valve 50 

Feed Valves 60 

Old Style Feed Valve 60 

Slide Valve Feed Valve 63 

Westinghouse Triple Valves ■. 68 

Plain Triple Valve 68 

Quick Action Triple Valve 74 

New Types of Triple Valves 84 

Type "K" Triple Valve 85 

Westinghouse Train Air Signal System 105-112 

Pressure Reducing Valve 105 



II CONTENTS 

Signal Valve 107 

Car Discharge Valve 108 

Defects of the Air Signal System no 

Combined Freight Car Cylinder and Auxiliary 

Reservoir With Triple Valve Attached. 113 

Automatic Slack Adjuster 116 

Pressure Retaining Valves 121-127 

Standard Retaining Valve , 121 

High and Low Pressure Retaining Valve 123 

Defects 01 the Retainer 126 

Combined Automatic and Straight Air Locomotive 

Brake Equipment 129-151 

Reducing Valve Pipe Bracket 133 

Straight Air Brake Valve , 134 

No. 2 Double Check Valve 138 

Type "E" Safety Valve 140 

Advantages of the Combined Automatic and 

Straight Air Brakes 143 

Defects of the Straight Air Brake 150 

Westinghouse Duplex Main Reservoir Control 152 

Double Pressure Control or Schedule "U" 154 

High Speed Brake 156 

High Speed Reducing Valve 159 

General Information Relating to High Speed 

Brake 164-165 

Reversing Cock . . . ' 165 

No. 6 ET Locomotive Brake Equipment . . . 170-244 

Manipulation 171 

Parts of the Equipment 174 

Names of Piping 175 

Arrangement of the Apparatus. 176 

Principles of Operation 180 

No. 6 Distributing Valve 183-207 

Automatic Operation 186 

Independent Brake Operation 197 



CONTENTS III 

Quick Action Cylinder Cap 202 

Defects of the Distributing Valve 204 

E-6 Safety Valve 207 

H-6 Automatic Brake Valve 210 

S-6 Independent Brake Valve 218 

B-6 Feed Valve 224 

C-6 Reducing Valve 228 

SF Type Pump Governor 229 

"Dead Engine" Feature 233 

Pump Failure When Double-Heading With ET 

Equipment 234 

Terminal Tests, and How to Locate and Remedy 
Defects of the Westinghouse No. 6 ET 

Equipment 235 

Air Gauge Test 235 

Brake Pipe Leakage Test 236 

Feed Valve Test 236 

Governor Test 237 

Automatic Brake Valve Test 238 

Independent Brake Valve Test 239 

Distributing Valve Test 240 

Brake Cylinder Leakage 243 

Safety Valve 243 

Signal Whistle Test 244 

NEW YORK AIR BRAKE AND SIGNAL 

SYSTEM 245-329 

Duplex Air Pump 245-259 

Automatic Oil Cup 252 

Defects of the Duplex Air Pump 255 

New York Air Pump Governors 260-265 

Style "C" Pump Governor 260 

Defects of the New York Pump Governors. . . . 264 

Duplex Pump Governor 262 

B3 Locomotive Brake Equipment 266-302 

Manipulation ' 268 



IV CONTENTS 

B3 Brake Valve 270 

Defects of B3 Brake Valve 281 

Supplementary Reservoir 282 

Divided Reservoir 283 

Pressure Controller 284 

Accelerator Valve 290 

Quick Release Valve . 294 

High Speed Controller 295 

Lever Safety Valve 297 

Terminal Tests and How to Locate Defects in the 

B3 Locomotive Brake Equipment 298 

B3 Engine Equipment 298 

Engineer's Brake Valve 299 

B2 Engineer's Valve. 300 

Pressure Controller 300 

Accelerator Valve 301 

High Speed Controller Valve . . 302 

New York Quick Action Triple Valves 303-318 

Passenger Quick Action Style "S" Triple Valve. 312 

Defects of the New York Triple Valves 315 

Style "A" New York High Speed Brake Compensat- 
ing Valve 319-324 

New York Train Air Signal System 325-329 

Signal Reducing Valve 325 

Signal Valve 326 

Defects of the New York Air Signal System. . . 328 

SUMMARY OF AIR BRAKE OPERATION 

AND TRAIN HANDLING 330-363 

Definition of the Air Brake. 330 

Tracing Air Through the Brake System 330 

Brake Pipe Pressure 331 

Excess Pressure 331 

Storage of Pressures 332 

Beginning and Ending of Pressure. ........... 333 

General Information Relating to Air Brake Practice . 335-363 



THE WESTINGHOUSE AIR BRAKE 

AND 

SIGNAL SYSTEM. 

Plate i shows the general arrangement of piping upon 
a locomotive and tender. Plate 2 shows a sectional view of 
the essential parts of the air brake system and their relative 
location, as follows : 

First. — The steam driven air pump, which supplies the 
compressed air. 

Second. — The main reservoir, in which the compressed 
air is stored. 

Third. — The engineer's brake valve, which regulates the 
flow of air from the main reservoir into the brake pipe for 
charging and releasing the brakes, and also from the brake 
pipe to the atmosphere for applying the brakes. 

Fourth. — The air gauge, which is of the duplex pattern 
and shows simultaneously the pressure in the main reservoir 
and that in the brake pipe. 

Fifth. — The pump governor, which regulates the supply 
of steam to the pump, stopping it when maximum pressure 
has been attained. 

Sixth. — The brake pipe, which connects the engineer's 
brake valve with the main reservoir, and also with each 
triple valve in the train, including the flexible hose and the 
couplings between the cars. 

Seventh. — The auxiliary reservoir, which is supplied 
with air from the main reservoir, through the brake pipe 
and triple valve. 

1 



2 WESTINGHOUSE AIR BRAKE. 

Eighth.— The brake cylinder and piston rod, which are 
connected to the brake levers in such a manner that when the 
piston is forced outward by the air pressure the brakes are 
applied. 

Ninth. — The quick action triple valve, which is con- 
nected to the brake pipe, auxiliary reservoir, brake cylinder 
and pressure retaining valve. It operates in accordance 
with the variations of pressure in the brake pipe : ( I ) to 
admit air from the auxiliary reservoir and the brake pipe to 
the brake cylinder, thereby applying the brakes, and at the 
same time to cut off communication from the brake pipe to 
the auxiliary reservoir; (2) to restore communication 
between the brake pipe and the auxiliary reservoir, and at 
the same time to discharge the air from the brake cylinder 
to the atmosphere, thereby releasing the brakes. 

Tenth. — The hose couplings, which are attached to 
flexible hose, and serve to unite the brake pipes of adjoining 
cars. 

Eleventh. — The pressure retaining valve, which, when 
used, prevents the complete discharge of the air from the 
brake cylinder, retaining a given pressure in the brake cylin- 
der when the brakes are released. . 

Twelfth. — The automatic slack adjuster, which auto- 
matically maintains a uniform travel of the piston in the 
cylinder by taking up the slack as the brake shoes wear 
away. 




£QUALIZINC 



==£= 



3RAKZ /»//»£- 



*=»//»,*- 7 I 




DF PIPI 




PLATE 1. GENERAL ARRANGEMENT OF PIPING UPON A LOCOMOTIVE AND TENDER 















■— ■ . :v 



















' 


























mmm 

1 



h 



iK 







PRESSURE RETAINING VALVE 




PLATE 2. GENERAL ARRANGEMENT OF WESTINGHOUSE AIR-BRAKE APPLIANCES ON FREIGHT EQUIPMENT 




THE ABOVE DIAGRAM IS SIMPLY ILLUSTRATIVE OF THE METHOD 

OF ARRANGING THE COMPRESSED AIR TRAIN SIGNALING APPLIANCES, 

AND MAY BE MODIFIED AS THE CONSTRUCTION OF THE ENGINE DEMAND 





PLATE 5. LOCATION OF TRAIN AIR SIGNAL SYSTEM 



WESTINGHOUSE AIR PUMPS. 

THE EIGHT-INCH AIR PUMP. 

Operative Parts. Fig. 3 shows the 8-inch air pump in 
its upward stroke. The principal operative parts of the valve 
gear are, the Steam Piston and Rod 10, the Air Piston 11, 
Piston Valves 7, Piston 23, Reversing Slide Valve 16, 
Reversing Rod 17 and Reversing Plate 18. Valves 30 and 
30 are the Air Discharge Valves, and 31 and 31 the Receiv- 
ing Air Valves. 

Operation — Steam End. The steam enters chamber 
m and port h, uniting chambers m and e, and conducts the 
steam from the former to the latter, which contains the 
reversing valve. 

When reversing slide valve 16 is in the position shown in 
Fig. 3, steam passes from chamber m, through port h, into 
chamber e x and thence through port a into chamber d, above 
reversing piston 23. The same steam pressure now acts 
downward upon piston 23 and lower piston valve 7, and 
upward on upper piston valve 7, but as the combined areas 
of piston 27, and lower piston valve 7 are greater than of 
upper piston valve 7 the steam forces piston 23 and piston 
valves 7 downward to the position shown. Steam is 
admitted to the cylinder through the upper ports in bushing 
26, raising piston 10. while the steam above piston 10 passes 
through the upper ports in bushing 25, thence through 
bushing f, f, shown by dotted lines, into chamber g and out 
at Y, through an exhaust pipe to the smoke arch, from which 
it is discharged to the atmosphere through the smoke-stack. 
When piston 10 has nearly completed its upward stroke, 

3 



WESTINGHOUSE AIR PUMPS. 




Fig. 3. 



WESTINGHOUSE AIR PUMPS. 5 

reversing plate 18 engages shoulder 11 and also raises revers- 
ing valve 16 to its uppermost position, in which port a is 
closed, and as the cavity in the valve connects ports b and c, 
the steam above piston 23 is discharged through port b, the 
cavity in reversing slide valve 16, port c and port /, /, into 
chamber g, and thence to the atmosphere through the 
exhaust pipe at Y. 

When piston 10 has nearly completed its downward 
stroke, the lower face of reversing plate 18 engages the 
button at the lower end of the reversing rod 17, drawing the 
reversing slide valve down, and the motion of the pump is 
again reversed. 

Operation — Air End. During the upward stroke of 
the pump the air above piston 1 1 is compressed and dis- 
charged through port p into the space between receiving 
valve 31 and discharge valve 30, forcing the latter from its 
seat and flowing through chamber t and port r, into chamber 
s and out at z to the main reservoir. 

The main reservoir pressure in chamber s holds lower 
discharge valve 30 upon its seat during the upward stroke 
of the pump, and, a partial vacuum being formed below 
piston II, lower receiving valve 31 is forced from its seat 
by atmospheric pressure, which then enters the lower part 
of the air cylinder. In the downward stroke of the pump 
the conditions are reversed; upper receiving valve 31 is 
lifted to fill the chamber above piston 1 1 as it descends, and 
the air compressed below the piston forces valve 30 from its 
seat and flows through chamber g and the pipe connected 
at z to the main reservoir. 

Valve Lifts. The receiving valve should have a lift 
of one-eighth of an inch and the discharge valves three 
thirty-seconds of an inch. 

Purposes of Operative Parts — Steam End. The 
steam portion of the air pump is practically a small engine, 
containing a steam cylinder, a main piston and valve gear, 



6 WESTINGHOUSE AIR PUMPS. 

so arranged as to admit and exhaust steam to and from, 
opposite sides of the steam piston. 

The purpose of the reversing valve piston 23 is to assist 
the smaller main valve piston 7 in overcoming the pressure 
of the large main piston 7, when moving the main valve to 
its lower position. 

The reversing slide valve 16 admits and exhausts the 
steam to and from the top of reversing piston 23. 

The reversing valve rod 17 raises and lowers reversing 
slide valve 16. 

The main valve piston 7 admits and exhausts steam to 
and from the cylinder. 

When the throttle is open, the steam pressure from the 
boiler is always constant upon the two inner faces of the 
main valve piston 7. 

Exhaust and atmospheric pressure is always present 
upon the two outer ends of the main valve piston. 

THE NINE AND ONE-HALF-INCH PUMP. 

Construction. The 9^2-inch pump is shown in Figs. 
4 and 5. The following description is applicable to either 
the right or the left-hand pump. The only difference 
between the two pumps is the location of the steam and 
exhaust connections, for convenience in piping. 

The valve gear of the pump consists of pistons yy and 
70 of unequal diameter, connected by rod 76, which imparts 
the movement of the pistons to slide valve 83, and this valve 
in turn controls the steam supply which operates the main 
steam piston 59. The reversing of pistons JJ and 79 is con- 
trolled by the reversing slide valve "/2 (Fig. 5), the duty of 
which is to admit and discharge steam to and from chamber 
D, at the right of piston yj. 

Chambers A and C are always in free communication 
through ports e, e. The reversing valve is operated by rod 



WESTINGHOUSE AIR PUMPS. 



Main Valve Bosmino 



•Fpipe TAP, 




Fig. 4. 



8 WESTINGHOUSE AIR PUMPS. 

yi, to which movement is imparted by reversing plate 69, 
which engages reversing button k on the downward stroke 
of the steam piston, and shoulder / on the upward stroke. 

Chamber E always communicates with the exhaust in 
order that no back pressure may occur when piston 79 is 
forced to the left, and that a partial vacuum may not' occur 
when the piston is forced to the right. The exhaust is made 
by means of port t, shown in the main valve bushing. This 
port leads from chamber E directly to the main exhaust port 
d, so that chamber E, at the left of piston 79, is always free 
from steam pressure. 

When the reversing slide valve 72 is in the position 
shown, chamber D is connected through ports h, h, reversing 
valve cavity H and ports f, f, with the main exhaust pas- 
sage d, d, and there is no pressure to the right of piston yy. 

Operation — Steam End. As steam enters the pump 
at X it passes through passage a 1 , a 2 , into chamber A, 
between pistons yy and 79. The area of piston yy being 
greater than that of piston 79, piston yy is force'd to the 
right, moving with it piston 79 and slide valve 83 to the 
position shown in Fig. 4, thus admitting steam below piston 
59, through port b, b l , b' 2 . Piston 59 is then forced upward 
and the steam above piston 59 passes through port c, c 1 , 
cavity B of slide valve 83, port d and passage d 1 , d 2 , to con- 
nection at Y, at which point it is discharged from the pump 
to the atmosphere through the exhaust pipe. 

When piston 59 reaches the upper end of its stroke, 
reversing plate 69 strikes shoulder j and rod 71, forcing it 
and the reversing slide valve y2 upward sufficiently to expose 
port g. Steam from chamber C then enters chamber D, 
through port g and port g 1 of the bushing (Fig. 4). The 
pressures upon the two faces of piston yy are thus equalized 
and the piston is balanced. The pressure in chamber A act- 
ing upon small piston 79 forces it to the left, moving with 
it piston yy and slide valve 83. 



WESTINGHOUSE AIR PUMPS. 



9 




, 




1 








115 


r „j 


















( 




: 




:• i 






1 ' 


)0WfP§$= 




— 63 


r 


M 


j?S« 


!#= 






- 


■••••/- 










- — - 










i f 




i 


















U,. 1 ". 1 ... 


64 







u3BT 

Fig. 5. 



io WESTINGHOUSE AIR PUMPS. 

With slide valve 83 in its extreme position at the left, 
steam from chamber A is admitted through port c 1 , c, above 
piston 59, forcing it downward. At the same time the steam 
below the piston is discharged to the atmosphere through 
port b 3 , b 2 , b 1 , b, chamber B of the slide valve, port d, d 1 , d 2 , 
and the exhaust pipe connected at Y. 

When piston 59 reaches the lower end of its stroke, 
reversing plate 69 engages reversing button k, moving it and 
the reversing slide valve downward to the position shown 
in Fig. 5, and one double stroke or cycle of the steam end 
of the pump has been traced. 

Operation — Air End. The movement of piston 59 is 
imparted to air piston' 66 by means of the piston rod. As 
piston 66 is raised, the air above it is compressed and air 
from the atmosphere is drawn in beneath it, the conditions 
being reversed in the downward stroke. 

As piston 66 is raised, the air above it is compressed and 
passes through port r, lifting discharge valve 86 from its 
seat. As the pressure below the valve is greater than the 
main reservoir pressure above it, the air passes down into 
chamber G, and thence into the main reservoir. The upward 
movement of the air piston produces a partial vacuum, which 
causes the lower left-hand receiving valve 86 to lift from its 
seat, and atmospheric pressure enters through the strainer 
at the air inlet and passes to chamber F, below the receiving 
valve, thence past the valve into port m, and into the lower 
end of the air cylinder, filling the cylinder. In the downward 
stroke of the pump the air passes the discharge valves to the 
main reservoir in the same manner as previously described. 

The receiving and discharge valves of the 9^2 -inch pump 
should each have a lift of three thirty-seconds of an inch. 

Diagrammatic Views. Figs. 6 and 7 show diagram- 
matic views of the 9^2 -inch pump, with all ports leading to 
and from the pump exposed, so that they can be plainly seen 
and the operation of the pump easily understood. Fig. 6 



WESTINGHOUSE AIR PUMPS. 



it 




'86c 



AIR 

I DIS CHARGE 



Fig. 6. 



12 WESTINGHOUSE AIR PUMPS. 

shows the pump on its upward stroke, and Fig. 7 on its 
downward stroke. 

Starting the Pump. When the pump is started it 
should be run very slowly, until it becomes warm and the 
condensed steam has worked out of the steam cylinders 
through the drain cocks and exhaust pipe, which will allow 
an air cushion to accumulate in the air cylinder. 

The lubricator should be put in operation immediately 
after the pump has been started. 

Lubrication — Steam and Air End. A swab well oiled 
should be kept on the piston rod. The amount of oil required 
in the steam cylinder of the pump depends largely upon 
the amount of work performed. Some pumps require 
more oil than others. Judgment should be used in 
determining the amount of oil required. 

Engine oil should never be used in the air cylinder, 
as it will eventually clog and restrict the air passages, 
causing the pump to heat and destroy its efficiency. 
Valve oil will give the best results, and should be sup- 
plied through the cup provided for that purpose. 

The pump should never be oiled through the air inlet 
or strainer, as this method of oiling tends to gum up the 
air valves and passages, and the cylinder receives but 
little benefit from the oil. 

A swab well oiled on the pump piston is beneficial, 
as it keeps the piston rod packing lubricated, and also 
assists in lubricating the air cylinder. 

SPEED OF THE PUMP. 

When descending long grades, the pump throttle 
should be opened sufficiently to keep the pump running 
fast enough to maintain the required pressure in the 
main reservoir. At other times the pump should be run 
fast enough to maintain the pressure, and the pump 
governor allowed to stop it at frequent intervals. It 



WESTINGHOUSE AIR PUMPS. 



13 




86r 



AIR 
DISCHARGE 



Fig. 7, 



i 4 WESTINGHOUSE AIR PUMPS. 

should not be run with a wide open throttle unless 
necessary, in order to keep up the required pressure. 

The maximum speed of an air pump should not 
exceed 120 single strokes per minute. A higher speed 
is detrimental to good service, as it does not allow the 
cylinder to fill with air at each stroke, and would event- 
ually cause the pump to run hot. 

The pump should not be run too slowly, as this 
allows the air that is being compressed to leak past the 
packing rings, preventing the air to enter the cylinder 
from the atmosphere in the regular manner. 

The pump" should not be run while the engine is 
standing over an ash pit or other places where it is 
likely to draw dust or other foreign matter into the air 
cylinder. 

DEFECTS OF THE EIGHT AND NINE AND ONE- 
HALF-INCH PUMPS. 

One of the frequent causes of stoppage of the 8-inch 
pump is the failure of oil to reach the reversing piston 23, 
which is due to its location. The trouble can be remedied 
by removing the reversing cylinder cap 21 (Fig. 3) and 
oiling the piston with valve oil. Before oiling, packing 
rings 24 should be examined, to ascertain whether they 
are in good condition. 

A broken reversing piston rod will cause a complete 
stoppage. Loose nuts on top or bottom of the main 
steam valve, the reversing plate 18, or the button on 
the lower end of reversing rod 17 becoming badly worn 
so that it fails to pull down the reversing valve, will also 
cause the pump to stop. 

Common causes of a pump stopping on the upward 
stroke are, a worn reversing plate 18, a worn shoulder 
on the reversing rod, broken stop pin 50, which would 
allow the packing rings to expand so that the pump 



WESTINGHOUSE AIR PUMPS. 15 

could not be reversed, piston 23 stuck in the bushing, 
or loose studs 51 on the reversing plate. 

If the pump stops on the down stroke it may be due 
to nuts 58 being off air piston 11, the button broken off 
of lower end of rod 17, or packing rings becoming dis- 
placed in reversing piston 23. 

If the nuts 58 are off the air piston, the bottom head 
should be removed and the nuts replaced. To prevent 
the piston from turning while replacing the nuts, cap 
nut 21 should be removed and the throttle of the pump 
opened slightly to admit a little steam to the top head. 

By the removal of cap nut 21, the steam which is 
admitted to the top of piston 23 is allowed to escape to 
the atmosphere. The large piston valve 7 overcomes the 
small piston valve, admitting steam to the top head of the 
pump, thus forcing the main piston downward and hold- 
ing it in that position. 

If the packing rings of piston 23 are broken, the 
broken parts should be removed and candle wicking 
substituted, cap nut 21 replaced and the pump started. 

If a pump stops before the maximum pressure is 
attained, the pump throttle should be shut off entirely 
for a few seconds and then opened quickly. If steam 
blows through to the exhaust and the pump fails to 
start, the main valve is probably broken. If the pump 
starts, but frequently stops again, the cap nut should 
be removed -and the parts oiled with valve oil, the cap 
replaced and the pump started slowly. If this fails to 
start the pump the reversing piston side cap should be 
removed, the packing rings examined to ascertain if they 
are broken, and if found broken the broken pieces should 
be removed and well-oiled candle wicking used as a sub- 
stitute. If this valve is found to be in good condition 
the center cap should be removed and the reversing valve 
and stem pulled out, noting whether the reversing plate 



16 WESTINGHOUSE AIR PUMPS. 

is solid. If these parts are in good condition they should 
be replaced, care being taken to put the valve in facing 
the reversing piston, pushing the stem down to its 
extreme limit and replacing the cap. If the pump now 
starts and makes one complete stroke up and down and 
again stops, the trouble may be caused by the working 
loose of the piston nut in the air end of the pump. The 
bottom air head should then be removed, the nut tight- 
ened up and the head replaced. 

Defective Air Valves. If the discharge valve is 
defective it will be manifested in the following ways : 

First. — By the pump working rapidly, but not pump- 
ing much air, the air from one end of the pump only 
being forced into the main reservoir. 

Second. — By an uneven stroke of the pump, the stroke 
moving away from the defective valve being the more 
rapid. 

Third. — Only a small volume of air will be drawn 
in at the inlet ports while the pump is making the quick 
stroke. 

In testing for this defect it can be determined by 
the air gauge, or by stopping the pump, opening the oil 
cups and removing the plug at the bottom of the cylinder 
head. If air continues to blow through the oil cup the 
upper discharge valve is leaking, while if air continues 
to blow through the opening in the cylinder head the 
lower discharge valve is leaking. 

In testing the air valves of an 8-inch pump, the hand 
should be held lightly over the air inlet ports ; if the air 
is drawn in and then forced out again at the upper or 
lower inlets it will indicate which valve is defective. 

If the receiving valve in the 9^-inch pump leaks, the 
hand should be placed lightly over the strainer. The 
suction will be decidedly less while the pump is making 



WESTINGHOUSE AIR PUMPS. 17 

the quick stroke, and the defective valve will be the one 
toward which the piston is traveling. 

If an air valve sticks it will be indicated, first, by an 
uneven stroke of the pump ; second, the pump will 
usually pound during the fast stroke ; third, the pump 
will heat; fourth, there will be no suction at the air 
inlet port during one stroke of the pump. 

When testing for this defect, the hand should be 
placed lightly upon the air inlet ; if the stroke of the 
pump is uneven and there is no suction when the pump 
is making the slow stroke, the receiving valve at the 
end of the cylinder from which the piston is moving 
is stuck shut, but if there is a suction when the pump is 
making the slow stroke, and no suction when it is making 
the fast stroke, the discharge valve at the end of the 
cylinder from which the piston is moving is stuck open. 

To remedy this defect the cages should be tapped 
lightly, and if this does not start the valve the air inlet 
strainer W should be removed in order to see whether 
the trouble is at that point. If the pump still fails 
to work properly, an examination of the air valves should 
be made. 

If one of the discharge valves is broken it -should 
be replaced with a new one, if there is one on hand ; if 
not, the receiving valve should be taken out and used 
to replace the broken discharge valve. This refers only 
to pumps in which all air valves are interchangeable, as 
with the 9^2-inch pump. The changing of the air valves 
is necessary in order that the pump may not labor 
against main reservoir pressure, which would be constant 
at one end of the piston, causing the pump to heat, and 
the constant pressure on the air piston would tend to 
leak past the packing rings and destroy the vacuum in 
the opposite end of the cylinder. The changing of the 
valves will cause the pump to give good service during 



18 WESTINGHOUSE AIR PUMPS. 

one stroke, and cold air will be drawn in through the 
broken receiving valve, which will prevent heating. 

The indication on the air gauge will show whether 
it is the receiving or discharging valve which is broken. 
If, when the brake valve is in running position, the red 
hand of the air gauge is raised and lowered at each 
stroke of the pump, it indicates that a discharge valve is 
broken or stuck open ; but if the red hand is raised once 
while the pump is making two strokes it indicates that 
a receiving valve is broken or stuck open. 

The pump will compress air in one direction only 
if any one of the four air valves is stuck or broken, 
the passages leading to or from the pump are stopped 
up, the piston rod packing blown out on the air end of 
the pump, the cylinder head plug gone, a cylinder head 
leaking on either end, or a top discharge valve bushing 
is loose on a g 1 /^ or u-inch pump. 

Leaky Air Piston Packing Rings. Leaky air piston 
packing rings will cause a pump to heat more quickly 
and become more troublesome than any other cause, due 
to the churning of the air in the cylinders. This defect 
can be detected by running the pump at a moderate 
speed and placing the hand lightly, so as not to exclude 
the air, over the air inlet ports, as air is drawn into the 
cylinder during the beginning or first half of each stroke, 
the cylinder being filled the balance of the stroke by air 
leaking past the defective rings. 

Failure of Pump to Restart Promptly. If the air 
supply is not maintained by reason of the pump failing 
to restart promptly, reduce the air pressure which the 
governor controls, and if the pump starts to work it 
indicates that the trouble is in the governor. If it does 
not start the fault is in the pump. 

How to Tighten a Loose Reversing Plate. In order 
to tighten a loose reversing plate the top head of the 



WESTINGHOUSE AIR PUMPS. 19 

pump should be removed, the cylinder head plug also 
removed, and a stick or rod used to shove the piston 
to the top end of its stroke. The reversing plate should 
then be fastened, and the reversing rod, top head and the 
lower cylinder head plug replaced. 

Heating of the Pump. Heating of the pump is often 
caused by badly gummed air valves, clogged ports due 
to the excessive use of oil in the air cylinder, which 
becomes mixed with dust that is drawn into the cylinder 
through the strainer, badly worn packing rings, racing 
of the pump, or pumping against a high pressure. 

Leakages and Blows in Eight-inch Pump. With an 
8-inch pump (Fig. 3), if the reversing valve 16 or its 
seat becomes worn so that it leaks, steam will now 
through ports c, f, f and £ to the exhaust, causing a 
constant blow. 

If the packing rings in either piston leak, steam will 
constantly escape by them into ports f, f, f, f, and thence 
into port g. 

Badly worn, broken or defective piston packing rings 
cause a constant heavy blow which is wasteful, as one 
end of the cylinder is always open direct to the exhaust, 
and the other end is always full of steam, thus giving a 
non-interrupted passage of the steam to the atmos- 
phere. Defective packing ring? should receive immediate 
attention. 

Leakages and Blows in the Nine and One-Half or 
Eleven-inch Pump. If slide valve 83 (Fig. 4) leaks, it 
will cause a constant blow through the exhaust while 
the pump is working. 

If the packing rings of piston valve 79 (Fig. 4) 
become worn or broken, causing them to leak, the result 
will be a constant blow, as steam will leak past piston 
79, into chamber E, through port t, which is always open 
to the atmosphere through the exhaust. 



20 WESTINGHOUSE AIR PUMPS. 

A leak in the gasket forming the joint between the 
top cylinder head and the cylinder will allow steam to 
pass from the supply passage directly through to the 
exhaust passage, but this seldom occurs without steam 
leaking to the atmosphere around the outside of the 
head, where it can readily be seen. This defect can be 
remedied by renewing the gasket. 

If the reversing valve (Fig. 7) leaks, there will be a 
constant blow 'of steam through port / into exhaust port d. 

If the top end of reversing rod (Fig. 6) becomes 
worn so that steam leaks past into port S and thence 
down through the reversing valve bushing passage into 
the top cylinder of the pump, it will cause a blow while 
the pump is making the upward stroke, as the exhaust 
passage of that end of the pump is then open. 

Pump Pounding. A pump will pound if it is not 
fastened firmly to its frame, if the air valves are stuck, 
or if there is too great a lift in the air valves. It will 
also pound if the reversing plate is badly worn and 
fails to reverse the pump at the proper point, or if the 
nuts on the piston are loose. The defects mentioned are 
the chief ones which cause pounding. 

THE EIGHT AND ONE-HALF-INCH CROSS- 
COMPOUND AIR COMPRESSOR. 

The building of more powerful locomotives with the 
ability to handle the long trains now in daily service 
throughout the country, as well as the large brake 
cylinders required for heavy freight and passenger cars 
of modern construction, have increased the demand for 
compressed air to such an extent that greater pump 
capacity has become essential on many roads where 
service conditions are especially severe. To meet this 
demand an air compressor of the cross-compound type 



WESTINGHOUSE AIR PUMPS. 



21 









fe_ 






Fig. 8. 



22 WESTINGHOUSE AIR PUMPS. 

has been developed. This type is not only of ample 
capacity for any railroad service, but in point of efficiency 
and economy in steam consumption it is a decided 
improvement over the present ^]/ 2 or n-inch air pumps. 
Fig. 8 shows a photographic view, and Plate 3, Figs. 1 
and 2, shows diagrammatic views of the air compressor. 
Operation — Steam End. Referring to Plate 3, Figs. 
1 and 2, steam enters passage a and passes to the top head, 
thence through passage b to the chamber above slide valve 
72 ; also through port / into the chamber above reversing 
valve 22. Consequently when the governor is open and 
steam is turned on at the compressor throttle, steam pressure 
is always present above slide valve 72 and reversing valve 
22. When the high pressure steam piston is at the bottom 
of its stroke, the reversing valve is in the position shown on 
Plate 3, Fig. 1. Port n is then uncovered, allowing the steam 
to flow to the chamber at the left of the large main valve 
piston 26. Port m, which also connects this chamber with 
the reversing valve seat, is closed by the reversing valve. 
Port is always in communication with port p and the 
exhaust passage e at one end, and the cylinder back of the 
small main valve piston 28 at the other end, so that the small 
main valve piston 28 always has exhaust pressure on its 
outer face. Since live steam is always in the chamber above 
slide valve 72 and exerts its pressure against the inner sur- 
face of both main valve pistons 26 and 28, and the larger 
piston now has full steam pressure on its outer face through 
port 11, the resulting pressure on it will be balanced, while 
the small piston has steam pressure on its inner face and 
exhaust on its outer, so that it will be forced to the right to 
the position shown on Plate 3, Fig. 1. Live steam can then 
pass through port k, which connects with the slide valve 
chamber at the side of the valve, and port g in the slide valve 
seat, leading to the bottom of the higli pressure steam cylin- 
der. At the same time, the top of the high pressure steam 



WESTINGHOUSE AIR PUMPS. 



23 



STEAM' 
EXHAUST. 



AIR DISCHARGE. 



STEAM INLET; 




4D 

Plate 3, Fig. 1. 



3B 



24 WESTINGHOUSE AIR PUMPS. 

cylinder is connected, through port c in the slide valve seat, 
ports h' and h in the slide valve, and port d in the slide valve 
seat, with the top of the low pressure steam cylinder. The 
high pressure steam beneath steam piston 7 will force it 
upward, while the steam above it will expand into the low 
pressure steam cylinder, forcing piston 8 downward. 

As the high pressure piston 7 approaches the upper end 
of its stroke, reversing plate 18 strikes the shoulder on 
reversing valve rod 21, forcing it and reversing valve 22 
upward. This movement closes port n, preventing any 
further flow of steam to the back of the large main valve 
piston. It also connects ports m and / by cavity q in the face 
of the reversing valve. Port / connects through port p with 
exhaust passage e, so that the chamber at the left of the 
large main valve piston 26 is connected to the exhaust. 

Under these conditions the outer faces of both main valve 
pistons are subject to exhaust pressure, while their inner 
faces have steam pressure as before. Since piston 26 is 
larger in diameter than piston 28, an excess of pressure 
exists toward the left, which moves pistons and main valve 
to the position shown on Plate 3, Fig. 2. It will be noted 
that port m enters the chamber at the left of the large main 
valve piston at a point which is not quite at the end of the 
chamber. This port is located at this point so that piston 26, 
when moving to the left, will close it before the piston reaches 
the limit of its movement. As port n is then closed by the 
reversing valve a small amount of steam is entrapped, which 
serves as a cushion to prevent this piston from striking the 
chamber cover. Port c in the valve seat now connects with 
port k in the main valve, so that live steam can pass to the 
top of the high pressure steam cylinder. At the same time, 
the bottom of the high pressure steam cylinder is connected 
through port g in the valve seat, ports h" and h' in the slide 
valve, and port f in the slide valve seat, to the bottom of the 
low pressure cylinder. The top of the low pressure cylinder 



WESTINGHOUSE AIR PUMPS. 



25 



STEAM NLET 




40 

Fig. 2, Plate 3. 



38 



26 WESTINGHOUSE AIR PUMPS. 

communicates through the cavity i in the slide valve and 
ports d and e in the seat with the exhaust. The high pres- 
sure steam piston is then forced downward by the steam 
entering through ports k and c from the boiler, and the low 
pressure piston is forced upward by the steam in the bottom 
of the high pressure steam cylinder expanding through ports 
g, h" , h! and /, into the bottom of the low pressure cylinder, 
while the low pressure steam above the piston passes out to 
the atmosphere through port d, cavity i, port e and the 
exhaust pipe connection. 

When the high pressure steam piston 7 reaches the bot- 
tom of its stroke, the reversing valve plate 18 strikes the. 
bottom on the lower end of reversing valve rod 21, pulling 
it and reversing valve 22 downward to the position shown 
on Plate 3, Fig. 1. Connection between ports / and m is 
again broken by the reversing valve 22 and port n opened. 
Thus the chamber at the left of the large main valve piston 
26 receives full steam pressure, equalizing the pressures on 
the two sides of that piston, and making the preponderance 
of steam pressure on the inner face of the small main valve 
piston force both pistons and slide valve to the right, when 
live steam is again admitted below the high pressure piston 
7 and the steam above the piston is connected to the top of 
the low pressure steam cylinder. The bottom of the low 
pressure steam cylinder is also connected through cavity i 
in the slide valve, and the ports / and e in the slide valve 
seat to the exhaust, so that the high pressure steam piston 
will start upward and the low pressure steam piston will be 
forced downward. Thus a complete cycle of the steam end 
of the compressor is finished. 

Operation — Air End. When the high pressure steam 
piston is forced upward, the low pressure air piston 9, being 
connected to the same piston rod, is also drawn upward, and 
air is drawn in through the lower suction strainer into the 
lower passage r' ( Plate 3, Fig. 1 ) . The inlet valve 38 then 



WESTINGHOUSE AIR PUMPS. 27 

lifts and the air passes into the cylinder through port s' . 
When this piston reaches the upper limit of its stroke, and 
starts downward, inlet valve 38 is forced to its seat, and the 
air below the piston is compressed until it can raise inter- 
mediate valves 40, when it is forced through ports t' and u' 
to the lower end of the high pressure air cylinder, the piston 
of which is being drawn upward in the meantime. When 
the low pressure air piston 9 reaches the lower limit of its 
stroke and starts upward, the intermediate valves 40 drop 
to their seat so that air from the high pressure air cylinder 
cannot flow back into the low pressure air cylinder. At the 
same time the high pressure piston 10 is forced downward 
by the low pressure steam piston, compressing the air that 
has been forced into the lower high pressure air cylinder 
from the low pressure side, until it is raised to a sufficient 
pressure to enable it to lift discharge valve 41, when it will 
be forced through port v' and passage w l to the air discharge 
connection. In this way the air is compressed in two stages, 
the intermediate pressure resulting from compressing the 
low pressure air cylinder which is filled with air at atmos- 
pheric pressure into the smaller high pressure air cylinder. 
The intermediate pressure which will result depends on the 
ratio of the low pressure to the high pressure cylinders, and 
is greatest at the end of the stroke. The air drawn in 
through the upper suction strainer to the top of the low pres- 
sure air cylinder passes through the compressor in exactly 
the same manner as that just described for the lower end, 
and, as the ports are lettered alike, its passage can readily 
be traced from the inlet to the discharge. It should be noted 
that the intermediate pressure above mentioned is inde- 
pendent of the delivery or main reservoir air pressure as long 
as the latter is the greater. This intermediate pressure is 
about 40 pounds. 



28 MAIN RESERVOIR. 

DEFECTS OF THE COMPRESSOR. 

A defective receiving valve 37 or 38 can be detected 
by holding the hand on or close to the strainer of these 
valves while the pressure piston is moving toward it. 
If it leaks, air will be felt blowing past it. 

If the compressor fails to restart promptly, after being 
stopped by the governor, the intermediate and discharg- 
ing valves should be examined and ground in if found to 
be leaking. 

Leakage past final discharge valves 41 and 42 can 
be detected by the slower movement of both the low 
and the high pressure pistons toward the leaky valve, 
and the quicker movement of the high pressure piston 
away from it. 

If too much oil is given to the low pressure cylinder 
it will collect on the intermediate air discharge valve, 
and will probably cause it to stick open. 

If the air pump runs hot it may be due to leaks by 
the piston rod packing; a leaky intermediate discharge 
valve ; a leaky receiving valve ; badly worn packing rings 
in the air end of the pump, or racing the pump under a 
high steam pressure. 

Other defects of the cross-compound air compressor 
are similar to those of the 9^-inch pump previously 
described. 

THE MAIN RESERVOIR. 

The principal purpose of the main reservoir is to 
afford an ample storage space for a supply of compressed 
air sufficiently large to release and recharge the brakes 
quickly. It also serves to entrap any dirt, water or other 
foreign substance which may be carried into the reservoir 
with the air, preventing them from being conveyed into 



MAIN RESERVOIR. 29 

the brake valve, triple valves and brake cylinders. The 
reservoir should be drained at frequent intervals. 

The atmosphere contains a great deal of moisture or 
water, which is carried in suspension. The greater the 
quantity of air compressed in a given space, the greater 
the amount of water which will accumulate. If no place 
were provided for the water to collect it would be 
carried with the current of air throughout the entire air 
system, preventing the brakes from working properly 
and freezing in winter, thus putting the entire brake 
system out of service. Only a small amount of this water 
results from leakage past the piston rod of the cylinder. 
The neglect of the engineman to drain the main reservoirs 
has been the direct cause of many air brake failures. 
An accumulation of water in the main reservoir is also 
a frequent cause of brakes sticking, especially on long 
trains, as the water takes up space in the reservoir that 
should be occupied by air. 

Capacity. The capacity of the main reservoirs varies 
from 20,000 to 66,000 cubic inches. 

Leakage. Leakage is about the only defect which the 
main reservoir is subject to, but a leak will rarely be 
found in the reservoir itself. All the piping from the 
pump and from the reservoir to the brake valve is con- 
sidered as a part of the reservoir, and it is in these pipes 
that the leaks usually occur. 



30 WESTINGHOUSE AIR PUMP GOVERNORS. 



WESTINGHOUSE AIR PUMP GOVERNORS. 



i PIPE 

TO MAIM RESERVOI 
CONNECTION 26 ON 
ENGINEER'S BRAKE. 
VALVE w 



TO BOILER 

X 




TO PUMP 

Y 



Fig. 10. 
AIR PUMP GOVERNOR- 



SINGLE. 



The location of the air pump governor in the brake 
system is shown on Plate 2. 

By following the direction of the arrows shown in 
Fig. io, which is a cross sectional view of the pump 



WESTINGHOUSE AIR PUMP GOVERNORS. 31 

governor with the valves in their normal position, it 
will be seen that the steam has a free passage from 
connection X to Y. 

Operation. The purpose of the governor is to cut off 
the steam supply, and thus practically stop the pump, 
when the desired air pressure in the main reservoir and 
brake pipe has been attained. The air pressure connec- 
tion to the governor is at W. The adjustment of the 
governor is regulated by means of adjusting nut 40, 
which regulates the tension of spring 41 upon diaphragm 
42. When the tension of spring 41 is greater than the 
air pressure in chamber a, the diaphragm holds the small 
pin valve 47 upon its seat; but when the air pressure 
underneath diaphragm 42 becomes greater than the ten- 
sion of spring 41, the diaphragm is raised, unseating the 
small pin valve. Air from chamber a then flows through 
passage b into the chamber above piston 28, and forces 
it downward, seating steam valve 26, and shutting off 
the steam supply from the pump. 

Whenever the air pressure becomes reduced, through 
leakage or otherwise, spring 41 forces diaphragm 42 
downward and the pin valve 47 is again seated. The air 
in the chamber above piston 28 then escapes to the atmos- 
phere through the small relief port C, and spring 31, 
assisted by the steam pressure below valve 26, raises 
piston 28 to its normal position, as shown on Plate 10. 
and the pump resumes operation. 

During the time that the pin valve is unseated, there 
is a continuous escape of air to the atmosphere through 
relief port C. This leakage, in conjunction with the 
leakage of steam through the small port d through steam 
valve 26, serves to keep the pump operating slowly, thus 
avoiding trouble from the condensation of steam, which 
would otherwise accumulate. 



32 WESTINGHOUSE AIR PUMP GOVERNORS. 

Number 35 is a drip pipe connection to the chamber 
immediately below piston 28. Its purpose is to permit 
any steam that may leak past the steam valve 26 or 
any air that may leak past piston 28 to escape to the 
atmosphere. To guard against the drip pipe freezing, 
the pipe leading from the connection E should be made 
as short as practicable. 

DUPLEX GOVERNOR WITH SIAMESE 
FITTINGS. 

Fig. 11 shows a sectional view of the duplex pump 
governor. By comparing Fig. 11 with Fig. 10 it will be 
seen that both the diaphragm bodies and the steam 
valve body of the duplex governor are exactly the same 
as the corresponding parts of the single governor. The 
only difference between the two governors is that the 
duplex governor is provided with the Siamese fitting 
and an extra diaphragm case. This governor is nothing 
more than a combination of two diaphragm bodies with 
one steam valve body, and it operates in the same 
manner as the single governor. Only one of the dia- 
phragms acts at a time, and therefore no further descrip- 
tion is necessary. Connection B of the pump governor 
leads to the boiler; connection P leads to the pump; 
connection MR leads to the main reservoir, and BV to 
the brake valve, as shown on Fig. n. 

On the D-8 brake valve the W connection leads to 
the brake pipe instead of the main reservoir. 

The normal position of the pump governor is open, 
as shown in Fig. 11. 

Cleaning and Changing Pressures. When for the 
purpose of cleaning it becomes necessary to relieve the 
pressure on a governor, which is connected directly to 
the brake pipe, with a D-8 brake valve, the cut-out cock 



WESTINGHOUSE AIR PUMP GOVERNORS 33 



MR 




op.ip pipe connection 
/*tor §"pipe 30 

35 



TO PUMP. 



Fig. 11. 



34 WESTINGHOUSE AIR PUMP GOVERNORS. 

below the brake valve should be turned and the pump shut 
off. The brake valve should be put in service position, 
the pressure drained from the governor, the tension on 
the regulating spring released, the spring casing removed 
and the governor cleaned with a piece of soft wood. 

To reduce the pressure with a single governor, with 
a G-6 brake valve, the cut-out cock below the valve 
should be turned, the main drum pressure drained either 
by using the bleed cock or taking off the handle of the 
brake valve, turning it upside down and turning the 
rotary so as to bring the large supply port a in com- 
munication with the direct application and emergency 
port. Or, the main reservoir can be drained by placing 
the brake valve handle in full release position and open- 
ing the angle cock on the rear of the tender. The first 
and second methods of draining are preferable, as foreign 
matter is not drawn through the brake valve. The tension 
of the regulating spring should then be released, the 
spring box disconnected from the governor body and 
the governor cleaned. 

The low pressure governor of the duplex, with the 
G-6 brake valve, in freight service, can be cleaned in the 
same manner as the governor with the D-8 brake valve. 

The pressure can be reduced from the high pressure 
governors of the duplex and the high speed in the same 
manner as the single governor with the G-6 brake valve 
previously described. 

To relieve the pressure from the low pressure gov- 
ernor of the high speed brake valve, the cut-out cock 
in the low pressure piping to the governor should be 
turned, and in all cases when the pressure of the governor 
is relieved the pump should be shut off when the pressure 
of the main drum is drained through the angle cock, and 
the brake valve should be reported as cleaned on the 
completion of the trip. 



WESTIXGHOUSE AIR PUMP GOVERNORS. 35 

Governor Inoperative. If the low pressure of the 
duplex governor in freight service becomes inoperative, 
a blind gasket should be placed in the pipe connections 
leading to the low pressure governor and the high pres- 
sure governor regulated to carry the required excess 
pressure. 

If the high pressure governor becomes inoperative, a 
blind gasket should be placed in the pipe connections 
leading to the high pressure governor and the pump 
throttled while the brake valve is on lap or in service 
position, or the piping can be changed from the high 
pressure to the low pressure governor, and from the low 
pressure to the high pressure governor, and a blind 
gasket placed in the pipe connections of the high pressure 
governor. 

The low pressure governor should then be regulated 
to carry the required excess pressure. 

If the high pressure governor of the high speed brake 
is inoperative, a blind gasket should be placed in the pipe 
connection leading to the high pressure governor, the 
low pressure governor then cut in and regulated to carry 
the high pressure required by the high speed brake. 

If the low pressure governor is defective, the cut-out 
cock in the pipe connection leading to the low pressure 
governor should be turned and the high pressure gov- 
ernor regulated to carry either the low or the high 
pressure as may be desired. 

Governor Cut Out. If the governor will not allow 
maximum pressure to be attained after all remedies have 
been applied as previously described, the air pipe leading 
to the governor should be disconnected, a blind gasket 
inserted between the pipe connections and the governor 
or the pipe connections at the brake valve, and the 
throttle used to regulate the speed of the pump during 
the remainder of the trip. 



36 WESTINGHOUSE AIR PUMP GOVERNORS. 

DEFECTS OF PUMP GOVERNORS. 

If pin valve 47 leaks, it will allow air pressure to flow 
in on top of air piston 28. Jf the leakage is greater than 
the amount of air escaping from the relief port C, the 
pressure will force the air piston down and completely 
stop the pump. 

Leaks in the governor can be detected by noting 
whether the air is escaping out of vent port C when the 
pump is working, which would indicate that the pin 
valve 47 is held from its seat by foreign matter. If no 
air blows out of vent port C, it should be noted whether 
air is leaking by the spring casing where it is attached 
to the body of the governor, or whether air is leaking 
out of the vent port in the spring casing, which would 
indicate a leak past diaphragm 42. 

If the governor allows too high a pressure, it may be 
due to the tension of regulating spring 41 being set too 
high, a leak by diaphragm 42 with the port in the spring 
casing stopped up, the strainer in the pipe connection to 
the governor becoming stopped up, the passageway lead- 
ing from the pipe connection to the chamber being 
stopped, passageway b becoming stopped up, governor 
piston 28 becoming stuck in the bushing, a stopped up 
waste pipe, scales under steam valve 26, steam valve 
becoming badly cut, pin valve 47 being too long, the 
head being off' the pin valve, or spring 48 broken. Any 
one of these defects will prevent the governor from 
operating and will allow the pump to continue working. 

If the pump stops before the maximum pressure has 
been reached it may be due to the tension of the regu- 
lating spring 41 being too weak, or the spring broken, 
pin valve 47 being held from its seat by foreign matter, 
or vent port C being stopped up. 



DUPLEX AIR GAUGE. 



37 



To distinguish whether the trouble is in the pump or 
the governor, if the pressure is not maintained, the 
pressure which controls the governor should be reduced. 
If the pump goes to work the fault is in the governor, 
but if the pump does not go to work all pressures should 
be reduced on the governor before attributing the fault 
to the pump. 

DUPLEX AIR GAUGE. 

The duplex air gauge shows simultaneously the pres- 
sure in the main reservoir and the brake pipe. One hand 
(usually colored red) indicates the main reservoir pres- 




Plate 4, Fig. 1. 

sure, while the other (colored black) shows the brake 
pipe pressure. It is in reality two gauges combined in 
one, the same dial serving for both hands. 

Description and Operation. Plate 4, Fig. 1, shows an 
exterior and Fig. 2 an interior view of the Westinghouse 
Duplex Air Gauge. Fig. 2 shows two bent tubes, A and B, 
elliptical' in shape. Tube B is connected to the fitting T, and 
tube A to fitting M. The bottom ends of the tubes are held 



38 



DUPLEX AIR GAUGE. 



fast and the top ends are sealed and free to move. Their 
action is thus explained. If a tube or an elliptical section is 
bent, and then filled with internal pressure, the force will 
tend to straighten the tube. This is due to the fact that an 
inner force of pressure tends to make the tube round. In 
assuming the round form, the concave side A of the bent 
tube tends to lengthen while the convex side tends to shorten. 
These combined effects tend to straighten the tube outward 




Fig. 2, Plate 4. 



and impart a movement to the free end. Tube A is con- 
nected to one end of lever k; g by means of link c. This 
lever is pivoted at e and the end / has the form of a toothed 
sector which meshes with a pinion on spindle i. Spindle i 
carries the red hand of the gauge and rotates within a hollow 
spindle l t which carries the black hand. Tube B is connected 
by link b to levers f and g at a point below the fulcrum or 



DUPLEX AIR GAUGE. 39 

pivot, so that the black hand will be turned in the same direc- 
tion as the red one. 

The lower ends of f and g have the form of a toothed 
sector which meshes with a pinion on hollow spindle / and 
operates the black hand. 

Testing Gauge. The air gauge can be tested by plac- 
ing the brake valve in full release position and watching the 
gauge while the pressure is being pumped up. If both hands 
do not move up together the gauge is out of order, as when 
the brake valve is in this position the main reservoir and 
brake pipe pressures remain equal. The two hands should 
register alike, but if they register within three pounds of 
each other the gauge may be considered as approximately 
correct. 



40 



ENGINEER'S BRAKE VALVES. 



ENGINEER'S BRAKE VALVES. 

THE D-8 BRAKE VALVE. 

The D-8 brake valve, being one of the old types of valves, 
has been superseded to a great extent by the more modern 
brake valves, causing the old types to become nearly obso- 
lete, though still used to some extent on small engines. 

Figs. 13 and 15 are sectional views of the brake valve in 
release position. Fig. 14 is a plan view of the rotary valve 
seat. 




Fig. 13. "D-8" Engineer's Brake Valve. 



A pipe connected at R (Fig. 13) leads to the red hand 
connection of the air gauge, and a pipe from W leads to the 
black hand connection. The pipe secured at T leads to the 
equalizing reservoir and the pipe from V connects the brake 
pipe with the pump governor. The brake pipe is connected 
at Y and air from the main reservoir enters the brake valve 



ENGINEER'S BRAKE VALVES. 



4i 



at X, and always has access to the chamber above rotary 
valve 13, its further course being governed by the position 
of the rotary valve. 

Positions. There are five different positions of the 
brake valve handle, namely, release, running, lap, service 
application and emergency application. As the engineer 



To Small Rcac*»a» 




Fig. 14. "D-8" Engineer's Brake Valve. 

faces the valve, the position farthest to his left is release, 
and the other positions follow to the right as illustrated, in 
the order named, with the exception of the lap position, 
which is to the left of service position. 

Release Position. When the brake valve is in release 
position, main reservoir air is conducted to the brake pipe 
at Y by supply port a in rotary valve 13, cavity b in its seat, 
cavity c, which in this position overlaps both cavity b, pas- 
sage, /, /, and passage b. Port / of the rotary valve registers 
with port e in the valve seat, so that chamber D above equal- 
izing piston 1 J and the equalizing reservoir, conected there- 
with through port S and the pipe secured at T, are in direct 
communication with the main reservoir (Fig. 15). Equaliz- 



42 



ENGINEER'S BRAKE VALVES. 



ing port g, shown by the dotted lines in Fig. 16, is in com- 
munication with cavity c of the rotary valve. Chamber D 
is also supplied through this port. If the brake valve is 
allowed to remain in release position a pressure of seventy 
pounds will exist in the main reservoir and throughout the 
brake system, and the governor will cause the pump to stop. 
The pump governor, being connected to the brake pipe, is 
adjusted to cut of! the steam supply as soon as the full brake 
pipe pressure has been secured. To obtain excess pressure 
in the main reservoir the brake valve handle must be moved 
to running position. 




Fig. 15. "D-8" Engineer's Brake Valve. 



Running Position. When the brake valve is in run- 
ning position, port j of the rotary valve registers with pas- 
sage f, leading to excess pressure valve 21, which is held to 
its seat by excess pressure spring 20, the tension of which is 



ENGINEER'S BRAKE VALVES 



43 



equal to a pressure of 20 pounds per square inch. Air from 
the main reservoir flows through port j into passage f, where 
it encounters the excess pressure valve, which is held to its 
seat by brake pipe pressure and spring 20. When the pres- 
sure in passage f exceeds that in the brake pipe by more 




Fig. 16. "D-8" Engineer's Brake Valve, Release Position. 

than twenty pounds, the excess pressure valve is forced from 
its seat, compressing spring 20, and the air flows through 
passages f and / into the brake pipe, as shown on Fig. 14. 
Port g, leading through the rotary valve seat to chamber D, 
still communicates with cavity c, which also overlaps pas- 
sage /, causing equalizations of the pressure in the brake pipe 
and chamber D, the latter being connected with the equaliz- 
ing reservoir as previously explained. With the brake valve 
handle in running position, the pump governor will cut off 
the steam supply when the brake pipe pressure reaches sev- 
enty pounds, but the interposition of the excess pressure 



44 ENGINEER'S BRAKE VALVES. 

valve has caused a pressure twenty pounds greater than that 
in the brake pipe to accumulate in the main reservoir, so that 
the main reservoir pressure is ninety pounds. 

Lap Position. 'When the rotary valve is in lap posi- 
tion, all ports are operatively blanked. If the pump is started 
with the valve in this position no air can reach the brake 
pipe to operate the pump governor, and the pump will con- 
tinue working until the main reservoir pressure has become 
about equal to the steam pressure in the boiler. 

Service Application Position. \\ hen the valve is in 
this position, communication between the main reservoir and 
the brake pipe, and also between the brake pipe and chamber 
D, is cut off, and the cavity in the lower face of the rotary 
valve connects port e with the small preliminary exhaust 
port h, whereby air is discharged from chamber D to the 
atmosphere. The resultant reduced pressure in. chamber D 
and the equalizing reservoir permits the greater brake pipe 
pressure below the equalizing piston to raise it, unseating 
the brake pipe discharge' valve. The brake pipe air then 
discharges through passage n into the atmosphere until the 
pressure becomes a trifle less than the pressure remaining in 
chamber D, which forces the piston downward, reseating 
the valve. 

Emergency Application Position. While the brake 
valve is in this position, cavity c of rotary valve 13 overlaps 
both the large "direct application and supply port" / and 
"direct application and exhaust port" k. A large direct pas- 
sage is thus provided for quickly discharging brake pipe 
pressure to the atmosphere, and the resulting sudden reduc- 
tion of brake pipe pressure causes an emergency application 
of the brake. 

Port e is slotted to the right (Fig. 14), this slot being 
provided in order that there may be no position between the 
release and running positions, in which communication 
between the main reservoir and the brake pipe is wholly cut 



ENGINEER'S BRAKE VALVES, 45 

off. If the rotary valve is so moved that port / is above the 
space between ports e and f, main reservoir air can still feed 
through the slotted port into chamber D, thence through port 
g, into cavity c of the rotary valve and through passage / 
into the brake pipe at Y. Port e also serves to allow the 
main reservoir pressure to reach chamber D above the 
equalizing piston when the valve handle is being moved to 
release position. The connection is established as soon as 
port j in the rotary valve comes into register with slotted 
port e in the rotary valve seat. 

Pressures. When the brake valve is in full release 
position there is one large direct opening leading from 
the main reservoir to the brake pipe, and two small ports 
open leading to chamber D (Fig. 16). 

There will be a pressure of seventy pounds accumu- 
lated in the main reservoir, chamber D and the brake 
pipe if the pump is started with the valve in this 
position. 

When the brake valve is moved to running position, 
air cannot pass to the brake pipe until excess pressure 
has been attained. In order for the air to pass to the 
brake pipe it must unseat the excess pressure valve, 
which cannot be done until the air pressure exceeds the 
tension of the valve spring. 

When this style of valve is in running position, there 
is a pressure of ninety pounds in the main reservoir and 
seventy pounds in the brake pipe. As soon as these 
pressures have been attained, the pump governor, which 
is controlled by brake pipe pressure, stops the pump. 

If the pump is started with the valve in running 
position, the red hand will go up to twenty pounds before 
the black hand moves. They should continue to raise 
twenty pounds apart, and stop with the red hand at 
ninety and the black hand at seventy pounds. 



46 ENGINEER'S BRAKE VALVES. 

DEFECTS OF THE D-8 BRAKE VALVE. 

If the rotary or excess pressure valve leaks the pump, 
after stopping, will not start again until the brake pipe 
and main reservoir pressures have been reduced below 
seventy pounds, or the pressure at which the governor 
is set. 

If no air will pass into the brake pipe when the brake 
valve is in running position, the trouble will be due to 
the excess pressure valve being stuck on its seat. When 
this occurs, the handle of the brake valve should be 
placed in full release position until the valve and cham- 
ber can be cleaned. 

If the red hand stands at eighty and the black hand 
at seventy pounds, when the pump stops, and the valve 
is in running position, the excess pressure spring is too 
weak. But if the red hand registers over ninety and 
the black hand at seventy pounds, the excess pressure 
spring is too strong. 

If the excess shows less than twenty pounds it should 
be adjusted. The cut-out cock below the brake valve 
should be turned, the brake valve placed in service 
position, the pump shut off and the spring taken out and 
pulled apart or stretched, so as to lengthen it, which will 
strengthen it. Or, a washer can be placed between the 
cap and the spring, to increase the tension. 

If the excess pressure is over twenty pounds it is 
evident that the spring is too long, or rather too strong. 
When this occurs a piece should be cut off the spring, 
and it is better to make several small cuts than one 
large one, or too much may be taken off by the first cut. 

At whatever pressure the pump governor may stop 
the pump, as long as the main reservoir pressure is 
twenty pounds in excess of the brake pipe pressure, the 
excess pressure spring has the right tension. 

If the red hand stands at eighty and the black hand 



EQUALIZING RESERVOIR. 47 

at sixty pounds or the red hand at one hundred and the 
black hand at eighty pounds, it indicates that the pump 
governor needs adjusting. 

If the brake valve fails to maintain excess pressure, 
the difficulty is caused either by a leaky rotary valve or 
by dirt accumulating on the seat of excess pressure 
valve 21. 

Distinguishing Leaks. A leaky rotary valve can be 
distinguished from a leaky excess pressure valve by 
placing the brake valve in lap position. If the pressure 
continues to equalize it will be a leaky rotary, but if the 
pressure does not equalize the trouble will be caused by 
a leaky excess pressure valve. 

Gauge Indications. When the brake valve handle is 
midway between the service and full emergency positions 
the black hand may show main reservoir pressure, 
although it is known by the position of the valve that 
there is no air in the brake pipe. This indication is due 
to the construction of the valve. When it is in this 
position, port / of the rotary stands over port g in the rotary 
seat, which leads to chamber D. Chamber D is charged to 
main reservoir pressure and the black hand registers 
chamber D pressure. 

EQUALIZING RESERVOIR. 

The small equalizing reservoir or brake valve reser- 
voir, commonly called the little drum (Fig. 17), is usually 
placed under the cab footboard. A pipe leads from this 
small drum to the engineer's valve which is connected 
at T, as shown on Fig. 13. The air can then pass 
through port ^ and chamber D. The equalizing reservoir 
serves to increase the capacity of chamber D, without 
an enlargement of the engineer's brake valve. Chamber 
D being of a small capacity, it would be impossible to 



4 8 



ENGINEER'S BRAKE VALVES. 



make a gradual service application of the brakes without 
the increased volume furnished by the little drum. 

The black hand of the air gauge is connected at the 
brake valve, and it therefore indicates chamber D and 
brake pipe pressures. The equalizing piston 17 separates 
chamber D from the brake pipe pressure. The pressure 
in chamber D acts in holding the equalizing piston down, 
and brake pipe pressure tends to force it upward. 




Fig. 17. 



Purpose of the Small Drum. The purpose of the 
small drum is to increase the volume of air on top of 
the equalizing piston in the engineer's brake valve. The 
air in the small cavity over the equalizing piston is 
sufficient to hold the piston to its seat, but there is not 
a sufficient volume to draw from when making a service 
reduction. 

If the engineer's brake valve was placed in service 
position and there was no equalizing reservoir to furnish 
an additional volume of air on top of the equalizing 
piston, the small volume of air on top of the piston 
would be exhausted in a flash, the black hand on the 
gauge would fall to the pin, the equalizing piston would 
raise full stroke and all of the brake pipe pressure would 



ENGINEER'S BRAKE VALVES. 49 

rush to the atmosphere through the brake pipe exhaust, 
causing the engineman to lose control of the brakes. 

Time Consumed for Preliminary Exhaust. When a 
service application of the brakes is made it will ordi- 
narily take from five to seven seconds to reduce chamber 
D pressure from seventy to fifty pounds, depending on 
the size of the equalizing reservoir. 

DEFECTS OF THE EQUALIZING RESERVOIR 
AND ITS CONNECTING PARTS. 

If the reduction from chamber D takes place too 
slowly it may be due to the preliminary exhaust port 
being partly stopped up, packing rings in equalizing 
piston leaking, gasket 32 leaking from main reservoir 
to chamber D, with the G-6 valve, or gasket 22. leaking 
from the brake pipe to chamber D, with the D-8 brake 
valve. 

If there is too rapid a reduction from chamber D it 
may be due to a leak in the pipe connection to the gauge, 
the bleeder in the small drum leaking, or the drum 
being partly filled with water, the preliminary port e 
being too large, or the choke being partly stopped up 
between chamber D and the small drum. 

Cutting Out the Drum. If the small drum springs a 
leak while on the road, a plug or a blind gasket should 
be put in the connection leading to it and the brake pipe 
exhaust plugged. The brake valve can then be used in 
the emergency application position for making service 
stops. The valve should be moved to the emergency 
port carefully in order to avoid quick action. When a 
service reduction has been made and the brake valve is 
being returned to lap position, it should be done carefully, 
in order to allow the port to be closed slowly and the 
surge of air from the rear portion of the brake pipe to 
escape to the atmosphere slowly, thus preventing the 



50 ENGINEER'S BRAKE VALVES. 

kicking off of the brakes on the head end of the train, 
which would otherwise cause the train to part, in 
addition to losing the braking power of the brakes so 
released. 



THE G-6 ENGINEER'S BRAKE VALVE. 

The D-5, E-6 and F-6 brake valves are practically 
identical, the different letters and figures simply referring 
to the same valve. The G-6 valve is also the same, 
except that the slide valve feed valve supplants the 
former feed valve attachment. 

Before describing the operation of the brake valve, 
it may be of benefit to the reader to define a few terms 
which are in common use. 

Excess Pressure. The difference between the pres- 
sure in the main reservoir and that in the brake pipe is 
usually from twenty to sixty pounds, when the train 
brake apparatus is fully charged. Excess pressure com- 
bined with an abundance of main reservoir capacity 
insures prompt release and recharging. The amount of 
excess pressure to be carried is determined by the char- 
acter of the road, length of train and size of main 
reservoir. 

Air Gauge Connections. The red hand of the gauge 
connection is piped to R (Fig. 18), and indicates main 
reservoir pressure. A tee is usually inserted in this pipe 
for a pipe connection to the pump governor, which is 
generally adjusted to cut off the steam supply when the 
main reservoir pressure has reached ninety pounds. The 
black hand of the gauge connection is piped to W, and 
is directly connected to the equalizer reservoir ; this hand 
also indicates the brake pipe pressure. The black hand is 
usually referred to as the brake pipe, and the red hand as 
the main reservoir pressure. 



ENGINEER'S BRAKE VALVES. 51 

Standard Pressures. The customary standard brake 
pipe pressure is seventy pounds, while ninety pounds is 
considered as standard main reservoir pressure, but these 
pressures may be modified to meet special conditions. In 
the following description seventy pounds w T ill be con- 
sidered the standard brake pipe pressure and ninety 
pounds the standard main reservoir pressure. 

Release Position. The purpose of this position is to 
provide a large and direct passage from the main reservoir 
to the brake pipe, thereby permitting a rapid flow of air into 
the latter, and insuring a quick release and recharging of 
the brakes. Release is the position shown in Fig. 18. By 
referring to Plate 2, it will be seen that a pipe leads from the 
main reservoir to the brake valve. It is connected at X 
(Fig. 18), and when the brake valve is in 'release position 
main reservoir air flows through passage A to the chamber 
above rotary valve 14, thence through port a in that valve, 
cavity b in its seat 3, cavity c in the valve (which overlaps 
cavity b) and passage /, /', to the brake pipe at Y. Port g, 
being then also exposed to cavity c, simultaneously conducts 
air into chamber D above equalizing piston 18. By means 
of passage S and a pipe connected at T, chamber D is always 
in open communication with the equalizing reservoir shown 
on Plate 2. Port ;' of the rotary valve registers with port e 
in its seat, and air is also conducted through these ports to 
chamber D. It thus occurs that in release position two small 
ports feed the equalizing reservoir and one large port sup- 
plies the brake pipe. 

The purpose of the equalizing reservoir with this valve 
is to increase the volume of chamber D above piston 18, and 
answers the same purpose as explained with the D-8 brake 
valve. 

While the brake valve is in release position, warning 
port r, shown by the dotted lines (Fig. 19), which is of very 
small area, discharges main reservoir pressure to the atmos- 



52' 



ENGINEER'S BRAKE VALVES. 



phere with considerable noise, attracting the engineer's 
attention if he subsequently neglects to move the valve to 
running position. If this brake valve were allowed to 
remain in release position a pressure of ninety pounds would 
result, not only in the main reservoir, but also in the equaliz- 
ing reservoir, brake pipe and auxiliary reservoirs, as in this 




Fig. 18. "G-6" Engineer's Brake Valve. 

position they are all in direct communication with each other. 
To stop the escape of air through the warning port and to 
prevent overcharging of the brake system, the valve is 
moved to running position. 

Running Position. This is the proper position of the 
brake valve when the brake apparatus is charged and ready 
for application. In this position (shown in Fig. 19) the 



ENGINEER'S BRAKE VALVES. 



53 



main reservoir pressure attains the proper excess above that 
in the brake pipe. This pressure is always present in the 
chamber above rotary valve 14 and is conducted bv port / 
and passages / and f into chamber F. Thence, as hereafter 
explained, its course is through the feed valve, from which 
it is conducted by passages i, / and /' into the brake pipe at 



25- 




sc 



Fig. 19. "G-6" Engineer's Brake Valve. 



Y (Figs. 20 and 21). Port g still connects chamber D with 
cavity c of the rotary valve, and, as cavity c still overlaps 
passage /, the equalizing reservoir and brake pipe are directly 
connected. The same pressure consequently exists above 
and below equalizing piston 18. The feed valve is adjusted 
to cut off the air supply to the brake pipe when the pressure 
reaches seventy pounds. The pump governor will not stop 



54 



ENGINEER'S BRAKE VALVES. 



the pump until the main reservoir pressure reaches ninety 
pounds. 

Lap Position. This position, the second from release, 
is that in which all ports are operatively blanked. After the 
preliminary discharge of air for a service application of the 
brakes, the valve handle is placed in lap position until it is 
desired to make a further brake pipe reduction, or to release 
the brakes. If the pump is started with the brake valve on 
"lap," the* result will be a pressure of ninety pounds in the 



16 w 




f 



20 

IS Mo Gauge j2v» 

— black hano— 
Train Pipe Pressuhe 



Fig. 20. "G-6" Engineer's Brake Valve. 



main reservoir and nothing in the brake pipe, when the pump 
is stopped by the governor. 

Service Application Position. This position is the 
third from release, and is used to cause a service application. 
A groove in the lower face of rotary valve 14 connects port 
e with groove h in its seat (Fig. 21), causing air to be dis- 



ENGINEER'S BRAKE VALVES. 



55 



charged from chamber D and the equalizing reservoir, 
through port k into the atmosphere, thus reducing the pres- 
sure above piston 18. The greater pressure in the brake 
pipe below the piston thereupon forces it upward and unseats 
the discharge valve, and brake pipe air discharges through 
port m and passages n and n' of the exhaust fitting, into the 
atmosphere. The desired reduction of pressure in chamber 




D having been made, the valve is moved back to lap posi- 
tion. It is to be observed, however, that after the valve has 
been moved to this position, air will continue to discharge 
from the exhaust fitting, until the pressure in the brake pipe 
has been reduced to a trifle less than that in chamber D and 



56 



ENGINEER'S BRAKE VALVES. 



the equalizing reservoir. Piston 18 then automatically forces 
the discharge valve to its seat, through the action of the 
greater pressure upon its upper surface. Ordinarily a reduc- 
tion of from five to eight pounds in brake pipe pressure is 
sufficient for an initial application of the brakes. 

Emergency Application Position. This position, 
which is the farthest from release, is used for an emergency 




application of the brakes. Direct application and exhaust 
port k and direct application and supply port / are directly 
connected by means of large cavity C in rotary valve 14, 
which in this position overlaps both, thus permitting a rapid 
discharge of brake pipe air through the large ports. The 



ENGINEER'S BRAKE VALVES. 57 

resulting sudden reduction of brake pipe pressure causes a 
nearly instantaneous application of the brakes throughout 
the train (Fig. 22). 

Difference in Types. The G-6 valve is the type most 
commonly used, but the D-8 type is also used to some 
extent, principally on light power. These two valves are 
alike in principle, and the same results are obtained by 
a differential construction of the valve, both valves 
having the same positions. 

The difference in the pipe connections of the two 
valves is, that on the G-6 valve the pipe leading to the 
pump governor is connected with the main reservoir 
pressure, while on the D-8 it is connected with the brake 
pipe. 

The G-6 has larger ports than the D-8 valve, and 
chamber D air is exhausted through the direct applica- 
tion and exhaust port ; it also has a warning port in the 
rotary, and a feed valve, with a pipe leading to governor 
connected to it, 

Regulation of Pressures. If the red, or main reservoir 
gauge hand, with a G-6 brake valve shows a pressure 
that is too high or too low, it is the fault of the governor, 
and it should be regulated by means of adjusting screw 
40. The tension of the screw should be slacked off for 
less excess pressure and tightened down for increased 
pressure. 

If the black, or brake pipe gauge hand, shows too 
high or too low pressure, the feed valve needs regulating. 
Cap 66 should be taken off and regulating nut 65 adjusted 
until the brake pipe pressure stands at seventy pounds. 

DEFECTS OF THE G-6 BRAKE VALVE. 

When the brake valve handle is in running position 
and the brake pipe pressure gradually increases, it indi- 
cates that air is leaking from the main reservoir into 



58 ENGINEER'S BRAKE VALVES. 

the brake pipe. This may be due to (i) the rotary valve 
leaking; (2) leaky gasket 32, allowing air to leak into 
chamber D and thence through the equalizing port to 
the brake pipe; (3) feed valve gasket 27 leaking; (4) 
diaphragm 43 leaking with vent port in spring box 
chamber 42 stopped up; (5) a leak past supply valve 34. 

Leaky Rotary. A leaky rotary valve would destroy 
excess pressure, as it will allow the main reservoir 
pressure to feed by the bridge of the rotary into the 
brake pipe, thus equalizing the brake pipe pressure with 
that in the main reservoir. This defect is considered 
dangerous at all times, particularly so if the engineman 
is not aware of the leakage. 

When applying the brakes with a leaky rotary, a 
sufficient reduction should be made to get the pistons 
past the leakage grooves, and a slight blow, sufficient to 
overcome the leakage from the main reservoir, should be 
allowed from the brake pipe exhaust, which will cause 
the black hand to fall gradually, until it is necessary to 
release the brakes or come to a stop. 

When testing for a leaky rotary valve or valve seat, 
the engine should be detached from the train, the brakes 
should be set with a reduction of from ten to fifteen 
pounds and the brake valve placed in lap position. If 
the black hand gradually creeps up and the brake releases, 
the rotary valve is leaking. 

Distinguishing Leaks. To distinguish between a 
leaky gasket 32 and a leaky rotary valve of the G-6 valve 
with the lone engine, the brake valve should be placed in 
service position, and all the pressure drained from the 
brake pipe and chamber D. If the blow continues at 
the direct application and emergency exhaust ports, the 
trouble is caused by gasket 32 allowing pressure to leak 
from the main reservoir across the gasket on top of 
equalizing piston 18. If the blow ceases at the emergency 



ENGINEER'S BRAKE VALVES. 59 

exhaust after the pressure has been reduced, and con- 
tinues at the brake pipe exhaust, the trouble is due to a 
leaky rotary valve. 

To distinguish between a leaky rotary valve and a 
leaky feed valve or gasket 27, the cut-out cock below 
the brake valve should be turned and the valve placed 
in lap position. If the pressures equalize it is a leaky 
rotary valve. If the hands remain separated on lap 
position, it is the feed valve or gasket 27. 

To distinguish between a leak from gasket 2J and one 
from the feed valve, the brake valve should be placed in 
service position and spring box 40, diaphragm and piston 
45 removed. The brake valve should then be placed in 
running position. If air blows by supply valve 34 it is 
the supply valve that is leaking, but if air blows out. of 
port i in the chamber B above piston 45, the leak is past 
gasket 2y. 

A leaky equalizing piston packing ring can be dis- 
tinguished from a leak at gasket 32, or the preliminary 
port being partly stopped up, by placing the brake valve 
in lap position with full pressure in the brake pipe and 
chamber D, and opening the brake pipe angle cock, 
draining the brake pipe. The leaky piston packing ring 
will then allow chamber D pressure to flow into the 
brake pipe and the gauge will indicate the leakage. Or, 
with a long train, after a reduction has been made in 
chamber D, the engineman should note whether the 
black hand gradually raises during the escape of air at 
the brake pipe exhaust and stops raising when the brake 
pipe exhaust ceases. If it does, it indicates that the 
equalizing piston packing rings are leaking. 

To distinguish a leaky gasket 32 from a partly stopped 
up preliminary port, place the brake valve in service 
position and draw off all of chamber D pressure. If the 
blow continues through the preliminary exhaust it indi- 



60 FEED VALVES. 

cates a leaky gasket 32, but if it ceases blowing it 
indicates a partly stopped up preliminary port. 

If the preliminary reduction is longer than from five 
to seven seconds with a long train, the reduction in the 
brake pipe will take place so slowly that it will not get 
the pistons past the leakage grooves on the rear cars. 

Equalizing Piston Packing Rings. If the packing 
rings are too tight, while reducing the pressure in chamber 
D, the brake pipe pressure will not respond until an 
unusually heavy reduction in chamber D pressure has been 
made, when the equalizing piston will suddenly raise (which 
would be likely to cause quick action of the brakes with a 
short train) ; also when the brake valve is on lap and there 
is a leak in the brake pipe, the gauge will not indicate it. 

The rotary valve, feed valve and excess pressure valve 
should be kept clean at all times in order that they may be 
in good working order, separating and maintaining their 
pressure properly. 

THE OLD STYLE FEED VALVE. 

Fig. 23 shows what is now usually known as the old 
style feed valve. 

When connected to the brake valve, passage /' registers 
with passage /' of the brake valve (Fig. 19), and passage i 
registers with passage i of the brake valve, which passage is 
connected with the brake pipe by means of passage I, V 
(Fig. 19) into w r hich it leads. 

Piston 45 of the feed valve is subject to the upward 
pressure of regulating spring 39, and to the downward air 
pressure in chamber B above the piston. The tension of 
spring 39 is so adjusted by regulating nut 41 that a pressure 
of seventy pounds (or any desired brake pipe pressure at 
which it may be set) is necessary in chamber B to overcome 
it and force the piston down. An upward movement of the 



FEED VALVES. 



61 




wmrm0 



Fig. 23. 



piston unseats supply valve 34, and a downward movement 
permits spring 35 to seat it. Chamber B always contains 
the same pressure as that in the brake pipe, as they are in 
open communication. 

When the brake valve is in running position and the 
pressure in chamber B is less than seventy pounds, regulat- 



62 FEED VALVES. 

ing spring 39 will raise piston 45 and unseat supply valve 
34. Air from the main reservoir, coming through passage 
f, passes supply valve 34 into chamber B, and there dis- 
charges, through passage i and the corresponding passage 
i in the brake valve, into the brake pipe. 

When the pressure in the brake pipe and chamber B 
reaches seventy pounds, it overcomes the tension of regulat- 
ing spring 39 and forces piston 45 downward, allowing 
spring 35 to seat supply valve 34, and no further passage of 
air can take place through the feed valve until the pressure 
in chamber B and the brake pipe becomes, by leakage or 
otherwise, so reduced that the regulating spring can again 
force the piston upward and unseat the supply valve. 

DEFECTS OF THE OLD STYLE FEED VALVE. 

A leaky supply valve may be caused by a damaged or 
imperfect seat, or foreign matter on the seat. If the trouble 
is caused by dirt, the valve should be held under an open 
gauge cock and then wiped off with a piece of clean waste. 
It should never, be scraped with a sharp instrument, as the 
valve seat is of soft metal, and the use of hard metal would 
be likely to scratch and ruin the seat. The best method of 
cleaning it is to use a piece of soft wood, with coal oil and 
waste. 

To remove the valve, it will be necessary to proceed as 
with the excess pressure valve of the D-8 brake valve. 

If spring box 40 (Fig. 23) is screwed up too tightly, or 
carelessly, diaphragm 43 is likely to be pinched off, squeezed 
out, or arched up in such a manner as to prevent the upward 
and downward movement of feed valve piston 45, thus pre- 
venting the supply valve from seating and allowing the main 
reservoir pressure to flow unobstructedly into the brake pipe 
until the pressures are equal. This leak can be detected by 
a waste of air at the relief port at the bottom of cap nut 42. 



FEED VALVES. 



63 



If the feed valve fails to separate or maintain the proper 
pressures, after all efforts to remedy the defect have failed, 
supply valve 34 should be removed and the governor regu- 
lated to carry seventy pounds, or whatever brake pipe pres- 
sure is desired. 

THE SLIDE VALVE FEED VALVE. 

Figs. 24 and 25 illustrate the device known as the slide 
valve feed valve, which may be used with either the D-5, 
E-6, F-6 or G-6 brake valve to maintain a predetermined 




63 62 

Fig. 24. 



65 



6 4 



FEED VALVES. 



brake pipe pressure while the brake valve is in running 
position. 

Fig. 24 shows a central section through the supply valve 
case and governor device, and Fig. 25 shows a central sec- 




Fig. 25. 

tion through the regulating valve and spring box, and a 
transverse section through the supply valve case. 

Ports /' and i register with ports in the brake valve 
designated by similar letters on Fig. 19,- and in running posi- 
tion the main reservoir pressure constantly has free access 



FEED VALVES. 65 

through passages f and / to chamber F. Chamber E, which 
is separated from chamber F by supply valve piston 54, is 
connected with passage i, and thus with the brake pipe, 
through passage c, c, port a and chamber G, above dia- 
phragm 57. Regulating valve 59 is normally held open by 
diaphragm 57 and regulating spring 67, the tension of which 
is adjusted by regulating nut 65, and when open chamber E 
is in communication with the brake pipe. 

When the handle of the brake valve is in running posi- 
tion, air pressure from the main reservoir in chamber F 
forces supply valve piston 54 forward, compressing its 
spring 58, carrying supply valve 55 with it and uncovering 
port b, thereby gaining entrance directly into the brake pipe 
through passage i, i. The resulting increase of pressure in 
the brake pipe and in chamber G above diaphragm 57 con- 
tinues until it becomes sufficient to overcome the tension of 
regulating spring 67, adjusted at seventy pounds. Dia- 
phragm 57 then allows regulating valve 59 to be seated by 
spring 60, thus closing port a, and cutting off all communica- 
tion between chamber E and the brake pipe. The pressures 
in chambers F and E then become equalized, through leak- 
age past supply valve piston 54, and supply valve piston 
spring 58, which is compressed by the relatively high pres- 
sure in chamber F, now reacts and forces supply valve 55 to 
its normal position, closing port b and cutting off communi- 
cation between the main reservoir and the brake pipe. A 
subsequent reduction of brake pipe pressure reduces the 
pressure in chamber G and permits regulating spring 67 to 
force regulating valve 59 from its seat, thereby causing the 
accumulated pressure in chamber E to discharge into the 
brake pipe. The equilibrium of pressure upon the opposite 
faces of supply valve piston 54 being thus destroyed, the 
higher main reservoir pressure in chamber F again forces 
it, together with supply valve 55, forward and recharges the 
brake pipe through port b. 



66 FEED VALVES. 

The lower portion of the slide valve feed valve is in 
principle and construction almost identically the same as 
the feed valve of the F-6 brake valve, and is subject to the 
greater portion of the latter's defects. The slide valve, or 
its upper part, requires very little attention other than an 
occasional cleaning and oiling. In order to clean the feed 
valve while the system is charged with air, it is necessary to 
proceed as with other types of the Westinghouse brake 
valve. 

DEFECTS OF THE SLIDE VALVE FEED VALVE. 

Defects of this type of feed valve that will result in over- 
charging the brake pipe are, slide valve 55 held from its seat 
by foreign matter, face or seat of the valve cut, piston 54 
stuck in the bushing with the slide valve open, the grooves of 
the loose fitting piston clogged up so as to make an air-tight 
fitting piston, spring 58 back of the piston chamber broken, 
cap nut 53 loose and leaking so that the air in chamber E 
can escape to the atmosphere (this will also allow the main 
reservoir pressure to hold the slide valve off its seat), regu- 
lating valve 59 held off its seat by dirt, spring 60 broken, 
tension of regulating spring 67 too great, or a leak by dia- 
phragm 57 with the hole in spring box 62 stopped up. Any 
of these defects will cause the brake pipe and main reservoir 
pressures to equalize. 

Defects in the feed valve that will prevent main reservoir 
pressure from feeding to the brake pipe when the brake 
valve is in running position are, improper adjustment of 
regulating spring 67, passage c, c, behind piston 54 becoming 
stopped up, thus allowing the pressures in chambers E and 
F to equalize and, with the aid of spring 58, keep slide valve 
55 closed, or piston 54 fitting too tightly in the bushing so 
that the main reservoir pressure cannot force it over and 
permit air to flow to the brake pipe. But if piston 54 is 
fitted too loosely in the bushing, a greater volume of air will 



FEED VALVES. 67 

pass the piston than can escape at regulating valve 59, and 
will result in holding supply valve 55 and piston 54 closed. 
If the trouble is due to improper adjustment of regulat- 
ing spring 67 it can be remedied by increasing the tension 
of the spring, but if it is due to passage c, c, being stopped 
up or piston 54 being stuck shut in the bushing, with the 
slide valve to its seat, piston 54 and slide valve 55 should be 
entirely removed, cap nut 53 replaced and the pump gover- 
nor regulated so that it will stop the pump at seventy pounds. 
If the duplex governor is used the ninety-pound governor 
should be regulated to seventy pounds. 



68 



WESTINGHOUSE TRIPLE VALVES. 



WESTINGHOUSE TRIPLE VALVES. 

THE PLAIN TRIPLE VALVE. 

The plain triple valve is now used on locomotives and 
tenders only, it having been superseded on all other classes 
of equipment by the quick action triple valve. 




Fig. 26. 

In the study of the triple valve, as well as other parts of 
the air brake or air signal equipment, a clearer understanding 



WESTINGHOUSE TRIPLE VALVES. 69 

will result if one starts at the problem by first asking himself 
the question, which is the greater or controlling pressure 
acting on the part in question? With this point thoroughly 
understood, the action of the parts under consideration can 
be readily traced; for example, if a brake pipe reduction is 
made, it is known that it will have the effect of lowering the 
pressure on the brake pipe side of the triple piston and cause 
the brake to apply. It is also known that when the brake 
pipe pressure is increased the tendency will be for the piston 
to move away from the greater brake pipe pressure, causing 
the brake to release. 

The different parts of the plain triple valve are shown on 
Plate 26 ; 13 is the cut-out cock and handle ; 8 the graduating 
stem ; 9 the graduating spring ; i and k are feed ports ; 5 is 
the triple piston ; 6 is the slide valve ; 7 is the graduating 
valve, which works inside the slide valve; 12 is the piston 
packing ring. The pipe connections leading to and from 
the triple valve are also shown in Fig. 26. 

Valve 13 permits the triple to be used as automatic air, 
or to be cut out entirely. 

The handle has two positions. The triple is cut in when 
the handle is standing at right angles to the triple. When 
the handle is placed at an angle of 45 degrees, ports r and e 
are blanked and the triple is cut out. 

There are several other kinds of triple valves beside the 
•old style plain triple with the cut-out cock in the body of the 
valve. The other plain triples are larger in proportion, with 
larger ports, and the cut-out cocks are in the cross-over pipe 
instead of in the body of the triple (Figs. 27 and 28). 

The normal position of the triple valve is release posi- 
tion, which allows the air to pass through the triple valve, 
charging the auxiliary reservoir. Air enters from the brake 
pipe connection (Fig. 28), passes through port e into grad- 
uating stem casting f, thence through port g to chamber h. 
The piston being in release position and feed port t in the 



70 



WESTINGHOUSE TRIPLE VALVES. 



bushing being open, the air is free to pass to port i in the 
bushing and port k in the piston shoulder to chamber m and 
thence through the pipe connection to the auxiliary at R. 



TO AUXLUWV RESERVOIR 




TO BRAKE PIPE 



Fig. 27. 

Service Application. In service application, the oper- 
ation of the plain triple valve is precisely the same as that 
of the quick action valve, which will later be described in all 
its various positions. To apply the brakes for a service stop 
a gradual reduction of brake pipe pressure is necessary, and 



WESTINGHOUSE TRIPLE VALVES. 71 

for the purpose of illustration the first reduction will be 
assumed to be of five pounds, thus leaving a pressure of 
sixty-five pounds to act upon the brake pipe face of main 
piston 5, while the original seventy pounds still acts upon the 
auxiliary reservoir face. As a result of this reduction the 
greater auxiliary reservoir pressure forces main piston 5 to 
the left. As the piston moves it closes feed grooves i, cutting 
off communication between the brake pipe and the auxiliary 
reservoir and unseats graduating valve 7, establishing com- 
munication between the transverse passages w and s of the 
slide valve, and when the graduating valve has become 
unseated, the collar at the end of piston stem u engages the 
slide valve, which is then drawn to the left during the 
further movement of the piston, thereby cutting off com- 
munication between exhaust cavity n in the slide valve and 
passage r leading to the brake cylinder. The movement of 
the main piston to the left is arrested by contact of its stem 
with graduating stem 8, which is held in position by grad- 
uating spring 9. In this position port z in the slide valve 
registers with port r, and auxiliary reservoir air flows 
through ports w and z of the slide valve and passage r to 
the brake cylinder. When the auxiliary reservoir -pressure 
has become slightly less than that (sixty-five pounds) upon 
the brake pipe face of the main piston, the greater brake 
pipe pressure forces the piston back sufficiently to seat the 
graduating valve, which is known as lap position. If it is 
desired to apply the brakes with greater force, a further 
brake pipe, reduction is made, which leaves the auxiliary 
pressure in excess of that in the brake pipe, and it again 
forces the main piston to the left and unseats graduating 
valve 7. The slide valve will not move, as the difference 
of pressure is just enough to overcome the friction of the 
piston and graduating valve, but not enough to overcome the 
friction of the slide valve. A corresponding further reduc- 
tion of brake pipe pressure results in the discharge of auxil- 



72 



WESTINGHOUSE TRIPLE VALVES. 



iary air to the brake cylinder. Such brake pipe reduction 
may be repeated until the auxiliary reservoir and brake 
cylinder pressures have finally become equalized, which will 
require a reduction of twenty pounds in the brake pipe. 



TO AUXILIARY 
RESERVOIR 



TO BRAKE CYLINDER 




TO BRAKE J»JP£ 



Fig. 28. 

The brake is then fully applied and any further brake pipe 
reduction is but a waste of air. 

Emergency Application. An emergency application 
is made by a sudden brake pipe reduction, which causes main 
piston 5 to move out so quickly that graduating spring 9 



WESTINGHOUSE TRIPLE VALVES. 73 

cannot withstand the impact of piston 5 against graduating 
stem 8, but yields so that the piston moves its full travel. 
In this position the upper edge of the slide valve is below 
the lower edge of the service port in the slide valve bushing, 
and an unobstructed communication between the auxiliary 
reservoir and the brake cylinder is secured through com- 
paratively large ports. Instead of passing through the slide 
valve passage, as in a service application, the air from the 
auxiliary reservoir entering the triple valve through a pipe 
connected at R, discharges directly into the brake cylinder 
through port r. During an emergency application, there- 
fore, the less restricted passages cause the full brake cylinder 
pressure to take effect more promptly, but the absence of 
the emergency parts in the plain triple results in no quick 
serial action and no greater final brake cylinder pressure 
than may occur in a service application. 

Release. To release the brakes the engineman admits 
main reservoir pressure into the brake pipe, thus increasing 
the pressure upon the brake pipe face of main piston 5 until 
it becomes greater than that upon the auxiliary reservoir 
face, and therefore forces the piston to its position at the 
extreme right. In this position the air in the brake cylinder 
is discharged through passage r, exhaust cavity n, into the 
slide valve and passage p to the atmosphere, either directly 
or through the pressure retaining valve when used. Feed 
groove i being again uncovered, the auxiliary reservoir 
becomes recharged. 

Cut-Out Cocks. The plain triple valve (Figs. 27 and 
28) has not the old style cut-out cock in the body of the 
triple. The triple valve is the same, however, except that it 
has not this part. When the straight air brakes were super- 
seded by the automatic, a lug was added to the four-way 
cock handle which will allow the brakes to be cut out of 
service if necessary, but it can no longer be converted into 
a straight air brake. On modern types of triple valves the 



74 WESTINGHOUSE TRIPLE VALVES. 

cock has been entirely eliminated and replaced with a cut-out 
cock in the cross-over pipe between the brake pipe and the 
triple valve. 

DEFECTS OF THE PLAIN TRIPLE. 

Blows of the plain triple valve may result from a leaky 
slide valve, the slide valve being held oiT its seat by foreign 
matter, or a leak from passage e to passage r, past the 
cut-out cock, with the old plain triple. 

To distinguish between a blow at the slide valve or the 
cut-out cock, a ten-pound reduction should be made. If the 
blow at the triple exhaust continues and the brake releases, 
it is the slide valve, but if the blow stops and the brake sets 
harder, and when the brake is released the blow starts again, 
the trouble is in the cut-out cock. 

THE QUICK ACTION TRIPLE VALVE. 

The quick action triple valve is located in the brake 
system as shown on Plate 2. 

This valve receives its name from the three distinct 
operations it performs in response to variations of brake 
pipe and auxiliary reservoir pressure, which are : ( 1 ) it 
charges the auxiliary reservoir; (2) applies the brakes; (3) 
releases the brakes. The various positions of the working 
parts of the triple valve in accomplishing these results are 
shown in Figs. 29, 30, 31 and 32. Fig. 33 is a perspective 
view of the slide valve and its seat. 

List of Parts. The various parts of the triple valve, as 
shown on Plate 29, are as follows : 
2. Triple Valve Body. 8. Emergency Piston. 



Slide Valve. 9. Emergency Valve Seat. 

Main Piston. 10. Emergency Valve. 

Piston Packing Ring. 11. Emergency Valve Rub- 
Slide Valve Spring. ber Seat. 

Graduating Valve. 12. Check Valve Spring. 



13- 


Check Valve Case. 


20. 


14- 


Check Y a 1 v e Case 


21. 




Gasket. 


22. 


15- 


Check Valve. 


23. 


i6. 


Strainer. 


28. 


19. 


Cylinder Cap. 


i ai 



WESTINGHOUSE TRIPLE VALVES. 75 

Graduating Stem Nut. 
Graduating Stem. 
Graduating Spring. 
Cylinder Cap Gasket. 
Emergency Valve Nut. 
I k. Feed Grooves. 

Strainer 16 is designed to exclude foreign matter from 
the triple valve. Piston 4 operates in response to variations 
of brake pipe and auxiliary reservoir pressures, to open and 
close feed groove i, and controls the movement of the slide 
valve and the graduating valve. The latter is secured to the 
piston stem by a pin, shown by the dotted lines. 

The graduating valve (in a service application), moved 
by the main piston, controls the flow of air from the auxiliary 
reservoir through ports W and Z of the slide valve. 

The slide valve, moved by the main piston, controls 
communication between the brake cylinder and the atmos- 
phere, between the auxiliary reservoir and the brake cylinder, 
and also between the auxiliary and the chamber above 
emergency piston 8. 

Charging. Air from the brake pipes enters the triple 
valve at a (Fig. 29) and flows through passages e, f, g and 
h, past the main piston, through feed grooves i in the bush- 
ing and k in the piston seat, and thence through chamber m 
to the auxiliary reservoir, as indicated. Air continues to 
flow from the brake pipe to the auxiliary reservoir until the 
pressures equalize, when the main piston is balanced. 

The main piston constitutes a movable partition wall, 
separating the brake pipe and auxiliary reservoir pressures, 
and in studying the operation of the triple valve under 
various conditions, the first essential consideration is always 
as to which face of the main piston is exposed to the 
greatest pressure, as this determines the direction in which 
it will move. The usual brake pipe pressure is seventy 



7 6 



WESTINGHOUSE TRIPLE VALVES. 




FROM BRAKE PIPE 



Fig. 29. 



WESTINGHOUSE TRIPLE VALVES. 77 

pounds, acting upon both faces of the main piston when 
the brake pipe and auxiliary reservoirs are fullv charged. 

Service Application. To apply the brakes for a 
service stop, a gradual reduction of brake pipe pressure is 
necessary, and for the purpose of illustration the first reduc- 
tion will be one of five pounds, thus leaving a pressure of 
sixty-five pounds to act upon the brake pipe face of the 
main piston, while the original seventy pounds still operates 
upon the auxiliary reservoir face. As a result of this 
reduction, the greater auxiliary reservoir pressure forces 
the main piston to the left. As the piston moves, it closes 
feed groove i, cutting off communication between the brake 
pipe and the auxiliary reservoir, and unseats graduating 
valve 7, establishing communication between transverse 
passage W and port Z of the slide valve. When the grad- 
uating valve has become unseated, the collar at the end of 
the piston stem engages in the slide valve, which is then 
also moved to the left by the further movement of the 
piston, thereby cutting off communication between exhaust 
cavity n in the slide valve and passage r leading to the 
brake cylinder. The movement of the main piston to the 
left is arrested by contact of its stem /' with graduating 
stem 21, which is held in position by graduating spring 22. 
In this position, port Z in the • slide valve registers with 
port r, and auxiliary reservoir air flows through ports W 
and Z of the slide valve and passage r to the brake cylinder 
at C (Fig. 30). When the auxiliary reservoir pressure has 
become slightly less than that (sixty-five pounds) upon the 
brake pipe face of the main piston, the greater brake pipe 
pressure forces the piston back sufficiently to seat the grad- 
uating valve as shown in Fig. 31. This is known as "lap" 
position. 

If it is afterwards desired to apply the brakes with 
greater force, a further brake pipe reduction is made, which 
again leaves the auxiliary reservoir pressure in excess of 



78 WESTINGHOUSE TRIPLE VALVES. 

that in the brake pipe, which will force the main piston to 
the left and unseat graduating valve 7. A corresponding 
further reduction of auxiliary reservoir pressure results, 
through the discharge of air into the brake cylinder. Such 
brake pipe reductions may be repeated until the auxiliary 
reservoir and brake cylinder pressures are equal. The 
brakes are then fully applied and any further brake pipe 
reduction is a waste of air. A total reduction of about 
twenty pounds causes the brake pipe auxiliary reservoir 
and brake cylinder pressures to equalize. 

Emergency Application. A gradual or service reduc- 
tion of brake pipe pressure causes the main piston to move 
to the left until stem j encounters stem 21, when the tension 
of the graduating spring prevents a further movement, but 
a sudden brake pipe reduction causes the main piston to 
move out so quickly that graduating spring 22 cannot 
withstand the impact of stem j, and yields so that the piston 
moves to the position shown in Fig. 32. In this position, a 
diagonal slot in the slide valve (Fig. 33) uncovers port t 
(indicated by dotted lines just below the letter Z), which 
admits air from the slide valve chamber to the chamber 
above emergency piston 8. Piston 8 is thereby forced 
downward and unseats emergency valve 10, allowing the 
pressure in the small chamber Y, above check valve 15, to 
escape into the brake cylinder. The brake pipe pressure 
almost instantly raises the check valve, and the brake pipe 
air rushes through chambers a and Y into the brake cylinder 
at C. Air from the auxiliary reservoir simultaneously flows 
through port S of the slide valve and passage r into the 
brake cylinder, but port S being very small in comparison 
with the passageway through chambers a, Y and C, only a 
small amount of auxiliary reservoir air reaches the brake 
cylinder before the brake pipe and cylinder pressures are 
equalized, allowing the check valve to seat and prevent the 
air from escaping from the cylinder to the brake pipe. It 



WESTINGHOUSE TRIPLE VALVES. 



79 




Fig. 30. 



8o 



WESTINGHOUSE TRIPLE VALVES. 




Fig. 31. 



WESTINGHOUSE TRIPLE VALVES. 



81 




Fig. 32 



%2 



WESTINGHOUSE TRIPLE VALVES. 



thus may be seen that in an emergency application an 
increased brake cylinder pressure is secured through the 
presence of the air supplied by the brake pipe, in addition 
to that from the auxiliary reservoir, which is the only source 
of air pressure for the brake cylinder during a service 
application of the brakes. 

The rapid discharge of air from the brake pipe into the 
brake cylinder, in addition to the sudden reduction made at 




Fig. 33. 



the brake valve, causes a similar operation of the triple 
valve upon the next car. The operation of that triple valve 
similarly affects the next, and so on, serially, throughout 
the train. 

Release. To release the brakes the engineman admits 
main reservoir pressure into the brake pipe, thus increasing 
the pressure upon the brake pipe face of the main piston 
until it becomes greater than that upon the auxiliary reser- 
voir side, and forcing the piston to its normal or release 
position, shown on Fig. 29. In this position the air in the 
brake cylinder is discharged through passage r, exhaust 
cavity n in the slide valve and passage p to the atmosphere, 
either directly or through the pressure retaining valve. 
Feed groove i being again uncovered, the auxiliary reservoir 
becomes recharged with air from the brake pipe. 

Purposes of the Triple Piston, Slide and Graduating 
Valves. The duty of the triple piston is to open and 



WESTINGHOUSE TRIPLE VALVES. 83 

close the feed groove and to guide the movement of the 
slide valve and graduating valve, and also to form a 
dividing line between the auxiliary reservoir and brake pipe 
pressures. 

The purpose of the slide valve is to open and close com- 
munication between the brake cylinder and the atmosphere 
and to open and close communication between the auxiliary 
reservoir and the brake cylinder in conjunction with the 
graduating valve and the triple piston. It is also the duty 
of the slide valve in the quick action triple to open and close 
communication between the auxiliary reservoir and the 
emergency piston, and between the auxiliary reservoir and 
the brake cylinder in conjunction with the triple piston. 

The duty of the graduating valve is to graduate the flow 
of air from the auxiliary reservoir to the brake cylinder. 

DEFECTS OF THE QUICK ACTION TRIPLE 

VALVE. 

Defects that will cause a blow at the triple exhaust are, 
the slide valve held off its seat by dirt, the slide valve seat 
cut, a defective gasket 15 between the auxiliary and the 
triple valve, defective gasket between the brake cylinder head 
and the triple valve, auxiliary tube b in freight equipment 
becoming cracked, defective check case gasket 14, or a 
defective rubber seated valve 10. 

A slide valve leak, defective gasket between the triple 
and auxiliary, cracked auxiliary tube b, or leaky gasket 
between the triple and brake cylinder would have the effect 
of reducing the pressure in the auxiliary reservoir and 
releasing the brake, while a leaky gasket 14 or a leak in 
the rubber seated valve 10 would reduce the brake pipe 
pressure and tend to set the brake with greater force. 

Distinguishing Leaks. To distinguish between the 
various blows at the triple exhaust, a ten-pound reduction 
should be made. If the blow stops, the brake sets harder, 



84 WESTINGHOUSE TRIPLE VALVES. 

then releases, and the blow then starts again at the triple 
exhaust, the trouble is due to a leak between the triple and 
auxiliary or between the triple and brake cylinder, or a 
cracked auxiliary tube b. But if, after making the reduc- 
tion, the blow continues and the brake releases, it would be 
due to a defective slide valve, while if the blow stopped at 
the triple exhaust, the brake set harder and did not release, 
it would indicate a leak at gasket 14 or at the rubber seated 
valve. 

A leaky bleeder of the auxiliary reservoir, a leak in the 
pipe connection leading from the triple valve to the auxiliary 
reservoir or the pipe connection leading from the triple 
valve to the brake cylinder, the packing leather in the brake 
cylinder becoming worn, the piston not covering the leakage 
grooves, or a leak between the brake cylinder head and the 
cylinder, will also release the brake. 

The effect produced by a leak at the graduating valve 
is uncertain and would depend on the conditions connected 
with it. When the brake is applied the triple valve assumes 
lap position. If the graduating valve leaks, the auxiliary 
pressure gradually reduces and the brake pipe pressure 
forces the piston and slide valve back until the blank on the 
face of the slide valve between ports Z and u is in front of 
port r. This blank space is only a trifle wider than port r. 
If the valve is in good condition and works smoothly the 
brake should not release, but if it works hard it is likely to 
jump when it moves, thus opening the exhaust port and 
releasing the brake. 

NEW TYPES OF WESTINGHOUSE TRIPLE 

VALVES. 

The greatly changed conditions in the operation of 
railway trains during the past few years, incident to the 
employment of locomotives capable of handling long 
trains of freight cars, as well as the large number of air 



WESTINGHOUSE TRIPLE VALVES. 85 

brakes in such trains, also the air brake requirements in 
connection with passenger trains, have created conditions 
which the well-known types of triple valves have in 
many instances proved unable to meet. 

By reference to cuts showing the arrangement of the 
ports in the slide valve, graduating valve and slide valve 
bushing of this new type of triple (Fig. 35), it will be 
noted that the general arrangement of ports is along each 
side of a longitudinal center line, rendering it somewhat 
difficult to follow the course of air through them with 
sectional views in which the actual arrangement of ports 
is shown. Diagrammatic cuts are used, therefore, for 
illustrating the valves in their several positions, all ports 
and passages having been so rearranged as to place them 
on a single plane. In preparing these cuts the actual 
proportion and mechanical construction of the valves 
have been sacrificed for the purpose of making them as 
easily understood as possible. 

In this new valve, the triple piston, slide valve and 
graduating valve are the same in their relation to each 
other as in the older well-known types of triples, the 
graduating valve, however, being of the sliding type and 
located on top of the slide valve. The triple piston 
constitutes a movable partition separating brake pipe 
and auxiliary reservoir pressure. To apply or release the 
brake, air pressure is reduced or increased until a suffi- 
cient differential is created on opposite sides of the piston 
to overcome the friction of the piston packing ring and 
slide valve. 

THE TYPE "K" TRIPLE VALVE. 

The new quick action freight triple valve, designated 
as type "K," facilitates train movements, increases the 
factor of safety in handling trains, and reduces damage 



86 WESTINGHOUSE TRIPLE VALVES. 

to lading and equipment in so far as they are affected 
by air brake operation. 

Improvements Over the Old Type Triple. The old 

type "H" quick~action freight triple valve was designed 
to meet the requirements of the time when fifty-car trains* 
thirty-ton capacity cars, and moderate speeds were maxi- 
mum conditions. But the increased train lengths, higher 
speeds and greater car capacities of the present age, 
have demanded certain modifications to meet these, and 
anticipate future requirements. 

The "K" triple valve embodies every feature of the 
old type and, in addition, three new ones called the 
Quick Service, Retarded Release and Uniform Recharge. 
It not only works in harmony with the old valve, but 
greatly improves the action of the latter when they are 
mixed in the same train. They have many parts in com- 
mon, are interchange ble, and the old type quick action 
triple can be converted into the new, without the loss of 
many parts. 

Quick Service. The quick service feature, which pro- 
duces a quick serial operation of the brakes in service 
application, has been obtained by utilizing the well- 
known principle of quick action in emergency applica- 
tions, by which each triple valve augments the brake 
pipe reduction by discharging brake pipe air into its 
brake cylinder. The essential difference is that in emer- 
gency the maximum braking power is always obtained 
with both the old and new types of valves, while with the 
new valve, the power of its quick service application is 
always under complete control and is governed by the 
reduction made at the brake valve. The result is that 
the quick service feature insures the prompt and reliable 
response of every brake, eliminates the undesirable use 
of emergency applications where an unforeseen danger 
ahead, or the need of making accurate stops frequently, 



WESTINGHOUSE TRIPLE VALVES. 87 

necessitates such applications with the old standard 
freight brake equipment, reduces the possible loss of air 
due to its flowing back through the feed grooves from the 
auxiliary reservoir to the brake pipe, or by the leakage 
grooves in the cylinders, and gives a more uniform appli- 
cation of the brakes throughout the train. 

Release Feature. The retarded release feature, which 
insures practically a uniform release of all brakes, has 
been effected by automatically restricting the exhaust of 
air from the brake cylinders at the head end of the 
train, and allowing all others to release freely. To obtain 
this result requires merely the usual correct method of 
operating the brake valve, the retarded release being due 
to the quick and considerable rise in brake pipe pressure 
which occurs in the brake pipe for about twenty-five or 
thirty cars from the locomotive in long trains. This is 
possible, for the reason that the frictional resistance to 
the flow of air through the brake pipe prevents the 
building up of brake pipe pressure in the balance of the 
train faster than it can flow into the auxiliary reservoirs. 
Recharging. The uniform recharge of the auxiliary 
reservoirs throughout the train is obtained by the fact 
that when the triple valve is in retarded release position, 
the charging ports between the brake pipe and the auxil- 
iary reservoir are automatically restricted. As long as 
the release of brake cylinder exhaust is retarded, the 
recharge is restricted, and since the one feature depends 
upon the other, the restricted recharge operates only on 
the first twenty-five or thirty cars back of the locomotive, 
the remaining brakes recharging normally, thus insuring 
practically a simultaneous recharge of all brakes in the 
train. 

This feature not only avoids the overcharge of the 
auxiliary reservoirs on the front cars, and the subsequent 
undesired reapplication of their brakes, but, by drawing 



88 WESTINGHOUSE TRIPLE VALVES. 

less air from the brake pipe, permits the increase in brake 
pipe pressure to travel more rapidly to the rear for the 
purpose of releasing and recharging those brakes. 

Sizes of Valves. The new valve is at present manu- 
factured in two sizes, the K-i for use with eight-inch 
freight car brake cylinders, corresponding with the H-i, 
and the K-2 for use with ten-inch freight car brake 
cylinders, corresponding with the H-2. The K-i will 
bolt to the same reservoir as the H-i, and the K-2 to the 
same as the H-2. Each valve is marked with its desig- 
nation on the side of the valve body, and the K-2 may 
be distinguished from the K-i by the fact that it has 
three, instead of two, bolt holes in the reservoir flange. 
Also, in order to distinguish the type "R" \ r alves from the 
old standard type, their exterior being similar when they 
are attached to the auxiliary reservoir, a lug is cast on 
top of the valve body. This enables anyone to dis- 
tinguish them at once. 

List of Parts. Fig. 34 shows a vertical cross section 
of this valve, and the names of the various parts, as 
follows : 



2. 


Valve Body. 


14. 


Check Valve Case 


3- 


Slide Valve. 




Gasket. 


4- 


Piston. 


15. 


Check Valve. 


5- 


Piston Packing Ring. 


16. 


Air Strainer. 


6. 


Slide Valve Spring. 


17. 


Union Nut. 


7. 


Graduating Valve. 


18. 


Union Swivel. 


8. 


Emergency Piston. 


19. 


Cylinder Cap. 


9- 


Emergency Valve 


20. 


Graduating Stem Nut. 




Seat. 


21. 


Graduating Stem. 


10. 


Emergency Valve. 


22. 


Graduating Spring. 


11. 


Emergency Valve 


23- 


Cylinder Cap Gasket, 




Rubber Seat. 


24. 


Bolt and Nut. 


12. 


Check Valve Spring. 


25- 


Triple Valve Cap 


13- 


Check Valve Case. 




Screw. 



WESTINGHOUSE TRIPLE VALVES. 



80 



26. Drain Plug. 

27. Union Gasket. 

28. Emergency Valve Nut. 

29. Retarding Device 

Bracket. 

30. Retarding Device 

Screw. 

31. Retarding Device 



32. Retarding Device 

Washer. 

33. Retarding Device 

Spring. 

34. Retarding Device 

Stem Pin. 

35. Graduating Valve 

Spring. 



Stem. 
Positions of Ports, Passages and Cavities. Fig. 35 
shows the relative positions of the ports and cavities in 
the slide valve, graduating valve and slide valve seat. 
As it is difficult to show all of these in a single section, 
diagrammatic cuts of the valve are used, showing it in 
each of its principal positions, all ports and passages 



TO AUXILIARY 
RESERVOIR • 



34^g 




FROM 

BRAKE 
PIPE 



90 WESTINGHOUSK TRIPLE VALVES.. 

having been so arranged as to place them on one plane. 
In preparing these cuts, the actual proportion and 
mechanical construction of the valve have been disre- 
garded for the purpose of making the connections of 
ports, and the operation of the valve more easily 
understood. 

Retarding Device. Referring to Fig. 34, the branch 
from the brake pipe connects at union swivel 18. The 
retarding device bracket 29 projects into the auxiliary 
reservoir, and by its construction free communication 
exists between the auxiliary reservoir and chamber R, 
in which slide valve 3 and graduating valve 7 operate. 
The retarding device stem 31, through its extension into 
chamber R and the action of its spring 33, forms the 
stop against which the stem of piston 4 strikes when it 
moves to release position, from right to left in the cut, it 
being shown in full release position. 

Openings. The opening marked "Tg Brake Cylin- 
der" comes opposite one end of the tube which leads 
through the auxiliary reservoir to the brake cylinder, 
when the valve is bolted in place on the end of the 
auxiliary reservoir. This opening in the triple valve 
leads to chamber X over the emergency valve 10 and 
under emergency piston 8. It also leads through port r to 
the seat under slide valve 3. The emergency piston 8 and 
the parts below it are the same as in the older quick action 
freight triple valve. Port y (shown by dotted lines) 
connects chamber Y, between check valve 15 and emergency 
valve 10, with port y in the valve seat (Fig. 34). 

(Note: Dotted lines are used to indicate a port or 
part which is hidden by other parts of the mechanism, 
and would not be seen when looking at the device from 
the point of view taken. Some examples of this are 
shown in Fig. 36). 

Ports. Port / connects the slide valve seat with the 



WESTINGHOUSE TRIPLE VALVES. 91 

chamber above emergency piston 8. Port p is the exhaust 
port to the atmosphere. Port / in the slide valve begins at 
the face as shown by the top view (Fig. 36), and passes 
around other ports in the valve to a smaller opening in the 
top. (Port j does not exist in the K-i triple valve, as will 
be explained later.) Port is similarly arranged, except 
that the openings in the top and bottom are alike in size. 
Port q runs directly through the slide valve, but is smaller 
at the top than at the face of the valve, and the smaller 
part is out of center with the larger part. Ports s and .2 
run through the valve and connect with cavities in the face ; 
port 2 also has a cavity at the top. 

Cavities. The face view 7 of the graduating valve 
shows that it has a small cavity v. This valve is of the 
slide valve type, and it seats on top of the slide valve, where 
it controls the upper ends of ports z, q, and /. The 
purpose of cavity v is to connect the upper ends of ports 
and q in a service application, which will be explained in 
detail later. 

As shown by the face view of slide valve, n is a long 
cavity, having a narrow extension at the right hand end. 
Thh cavity connects the ports through which the air 
escapes from the brake cylinder in releasing. Port b is cut 
diagonally from the face until it just cuts into the edge, at 
the top of the slide valve. It admits auxiliary reservoir 
pressure to port t in an emergency application. 

With this explanation and by occasional reference from 
the diagrammatic views to those in Fig. 35, the same ports 
being lettered alike, a clear understanding will be obtained 
of both the operation and actual arrangement of the ports 
of the triple valve. 

Full Release and Charging Position. Fig. 36 is a 
diagrammatic view of the triple valve in this position. Air 
from the brake pipe flows through passage a to e and 
cylinder cap f, and ports g to chamber h; thence through 



9 2 WESTINGHOUSE TRIPLE VALVES, 



9" 



face: view 



GRADUATING VALVE 



a 



g i ^> 



ml 






FACE VIEW 






TOP VIEW 

SLIDE VALVE. 



kmmmm:mm^ 






^^^^^^^^^^^ 



SLIDE VALVE'BOSH. 

Fig. 35. 



WESTINGHOUSE TRIPLE VALVES. 



93 



feed groove i, now open, to chamber R above the slide valve, 
which is always in free communication with the auxiliary 
reservoir. The feed groove is of the same dimension as 
that of the old standard H-i triple valve, which is designed 
to charge the auxiliary reservoir of an eight-inch brake 
cylinder properly, and prevent any appreciable amount of 




W//////////////// A 



&2r\ 



^J 



R m 

"^'"'"1 



W///////// / //// /A 



Fig. 36. 



air from feeding back into the brake pipe from the auxiliary 
reservoir during an application. For this reason, the feed 
groove of the K-2 triple valve is made the same size as the 
K-i, so that it is necessary in the K-2 triple to increase the 
charging port area, through which the air can feed into the 
auxiliary reservoir, sufficiently to enable it to handle the 
greater volume of the auxiliary reservoir of a ten-inch brake 
cylinder. In order to do this, the small port / is added to 



94 WESTINGHOUSE TRIPLE VALVES. 

the slide valve of the K-2 triple valve only ; this port 
registers with port y in the slide valve seat, when in full 
release position. Air then passes from chamber Y, through 
ports y and j, to chamber R and the auxiliary reservoir. 
Brake pipe air then raises check valve 15 and supplies 
chamber Y with air as fast as it is required. Port / is so 
proportioned that the rate of charging the auxiliary reservoir 
of a ten-inch brake cylinder is made practically the same as 
that of the eight-inch, which in full release is fed through 
the feed groove i only. 

In the following description the K-2 triple valve only is 
referred to ; the operation of the K-i is exactly the same 
except for the absence of port /. 

Air flows from the brake pipe to the auxiliary reservoir 
until their pressures become equal, when the latter is then 
fully charged. 

Quick Service Application. To make a service 
application of the brakes, air pressure is gradually reduced 
in the brake pipe, and thereby in chamber h. As soon as 
the remaining pressure in the auxiliary reservoir and cham- 
ber R becomes enough greater than that in chamber h to 
overcome the friction of the piston 4 and graduating valve 7, 
these two move to the left until the shoulder on the end of 
the piston stem strikes against the right-hand end of the 
slide valve, when it also is moved to the left until the piston 
strikes the graduating stem 21, which is held in place by the 
compression of graduating spring 22. The parts of the 
valve are then in the position shown in Fig. 37. The first 
movement of the graduating valve closes the feed groove i, 
preventing the air from feeding back into the brake pipe 
from the auxiliary reservoir, and also opens the upper end 
of port z in the slide valve, while the movement of the latter 
closes the connection between port r and the exhaust port p, 
and brings port 3 into partial registration with port r, in the 
slide valve seat Auxiliary reservoir pressure then flows 



WESTINGHOUSE TRIPLE VALVES. 



95 



through port s in the slide valve and port r in the seat to 
the brake cylinder. 

At the same time the first movement of the graduating 
valve connected the two ports o and (7 in the slide valve, by 
the cavity v in the graduating valve, and the movement of 
the slide valve brought port to register with port y in the 



y////////////////////A 



mz%^mm% 




Fig. 37. 

slide valve seat, and port q with port t. Consequently, the 
air pressure in chamber Y flows through ports 3', 0, v, q and 
t, thence around the emergency piston 8, which fits loosely in 
its cylinder, to chamber X and the brake cylinder. When 
the pressure in chamber Y has reduced below the brake pipe 
pressure remaining in a, the check valve raises and allows 
the brake pipe air to flow by the check valve and through 



96 WESTINGHOUSE TRIPLE VALVES. 

the ports above mentioned to the brake cylinders. The size 
of these ports is so proportioned that the flow of air from 
the brake pipe to the top of emergency piston 8 is not 
sufficient to force the latter downward and thus cause an 
emergency application, but at the same time takes consid- 
erable air from the brake pipe, thus increasing the rapidity 
with which the brake pipe reduction travels through the 
train. 

Advantages of the New Type Triple Valve in Quick 
Service Application. With the old style quick action 
triple valve in service application, all of the brake pipe 
reduction is made at the brake valve, and the resulting 
drop in pressure passes back through the train at a rate 
depending on its length, size of brake pipe, number of 
bends, corners, etc., which cause friction and resistance. 
A much heavier application of the head than of the rear 
brakes is also caused at the beginning of the application, 
thereby running the slack in, which is liable at low speeds 
to be followed by the slack running out suddenly when 
the rear brakes do apply, causing loss of time and diffi- 
culty in making quick slow-downs and accurate stops, 
and, with very long trains, results in such serious losses 
through leakage grooves and feed grooves as to lose a 
portion of the braking power and even prevent some 
brakes from applying. With this new triple valve, only 
a small part of the reduction is made at the brake valve 
while each triple acts momentarily as a brake valve to 
increase the reduction under each car, thereby rendering 
the resistance and friction in the brake pipe of much less 
effect, and hastening the application throughout the 
train. This is called the "Quick Service" feature, and by 
means of it the rapidity of a full service application on a 
fifty-car train is increased about fifty per cent. The rapid 
reduction of brake pipe pressure moves the main piston 4 
quickly to the service position and cuts off any flow back 



WESTINGHOUSE TRIPLE VALVES. 97 

from the auxiliary reservoir through the feed groove to 
the brake pipe ; it rapidly drives the brake cylinder piston 
beyond the leakage groove and prevents loss of air 
through it, and yet permits the applying of brakes with 
as moderate a brake force as desired. It also greatly 
reduces the brake pipe reduction necessary at the brake 
valve for a certain brake cylinder pressure, due to the 
fact (1) that part of the reduction takes place at each 
triple valve, and (2) that the air taken from the brake 
pipe into the brake cylinder gives a little higher pressure 
than if the auxiliary reservoir pressure alone were 
admitted, thus requiring a smaller brake pipe reduction 
for the same cylinder pressure. 

Full Service Position. With short trains, the brake 
pipe volume, being comparatively small, will reduce more 
rapidly for a certain reduction at the brake valve than 
with long trains. Under such circumstances the added 
reduction at each triple valve by the quick service feature 
might bring about so rapid a brake pipe reduction as to 
cause quick action and an emergency application, when 
only a light application was intended. But this is 
automatically prevented by the triple valve itself. From 
Fig. 38 it will be noted that in the quick service position, 
port z in the slide valve and port r in the seat do not fully 
register. Nevertheless, the opening is sufficient to allow 
the air to flow from the auxiliary reservoir to the brake 
cylinder with sufficient rapidity to reduce the pressure in 
the auxiliary reservoir as fast as the pressure is reducing 
in the brake pipe, when the train is of considerable length. 
But if the brake pipe reduction is more rapid than that 
of the auxiliary, the difference in pressures on the two 
sides of piston 4 soon becomes sufficient to compress the 
graduating spring slightly, and move the slide valve to 
the position shown in Fig. 38. In this position, quick 



9 8 



WESTINGHOUSE TRIPLE VALVES. 



service port y is closed so that no air flows from the brake 
pipe to the brake cylinder. 

The brake pipe reduction being sufficiently rapid, 
there is no need of the additional quick service reduction, 
so the triple valve cuts it out. Also ports z and r are 
fully open, and allow the auxiliary reservoir pressure to 
reduce more rapidly, so as to keep pace with the more 
rapid brake pipe reduction. 

f 




Fig. 38. 



Lap Position. When the brake pipe reduction ceases, 
air continues to flow from the auxiliary reservoir through 
ports z and r to the brake cylinder, until the pressure in 
chamber R comes less than that of the brake pipe to cause 
piston 4 and graduating valve 7 to move to the right until 



WESTINGHOUSE TRIPLE VALVES. 



99 



the shoulder on the piston stem strikes the left-hand end 
of slide valve 3. As the friction of piston and graduating 
valve is much less than that of the slide valve, the differ- 
ence in pressure which will move the piston and the grad- 
uating valve will not be sufficient to move all three ; con- 



B 



mm 



Y/////////////////M 



Fig. 39. 

sequently the piston stops in the position shown in Fig. 39. 
This movement has caused the graduating valve to close 
port z, thus cutting off any further flow of air from the 
auxiliary reservoir to the brake cylinder. Consequently 
no further change in air pressure can occur, and this 
position is called "lap" because all ports are lapped ; that 
is, closed. 

If it is desired to make a heavier application a further 
reduction of the brake pipe pressure is made and the 




ioo WESTINGHOUSE TRIPLE VALVES. 

operation described above repeated, until the auxiliary 
reservoir and brake cylinder pressures become equal, after 
which any further brake pipe reduction is only a waste 
of air. About twenty pounds brake pipe reduction will 
give this equalization. 

Retarded Release and Charging Position. The "K" 
triple valve has two release positions, full release and 
retarded release. Which one of its ports will move when 
the train brakes are released depends upon how the 
brake pipe pressure is increased. If slowly it will be full 
release, and if quickly and considerably it will be 
retarded release. 

It is well known that in freight train service, when 
the engineer releases the brakes, the rapidity with which 
the brake pipe pressure increases on any car depends on 
the position of the car in the train. Those cars toward 
the front receiving the air first will have their brake 
pipe pressure raised more rapidly than those in the rear 
with the old standard apparatus. This is due to two 
things, (i) the friction in the brake pipe; (2) the fact 
that the auxiliary reservoirs in the front at once begin 
to recharge, thus tending to reduce the pressure head 
by absorbing a quantity of air and holding back the flow 
from the front to the rear of the train. The retarded 
release feature of this new triple valve overcomes the 
second point mentioned, taking advantage of the first 
while doing so. The friction of the brake pipe causes the 
pressure in chamber h to build up more rapidly on triple 
valves toward the front than those in the rear. As soon 
as its pressure is enough greater than auxiliary reservoir 
pressure, remaining in chamber R after the application 
above described, to overcome the friction of the piston, 
graduating valve and slide valve, all three are moved 
toward the right until the piston stem strikes the retard- 
ing device stem 31. The latter is held in position by 
the retarding device spring 33. If the rate of increase 



WESTINGHOUSE TRIPLE VALVES. 



IOI 



of the brake pipe pressure is small, as, for example, when 
the car is near the rear of the train, the triple valve parts 
will remain in this position, as shown in Fig. 36, the 
brakes will release and the auxiliary reservoirs recharge 
as described under "Full Release and Charging." If, 




V//////////////////;a 



R m 



31 






y//////////////////A 



Fig. 40. 



however, the triple valve is near the head of the train, 
and the brake pipe pressure builds up more rapidly than 
the auxiliary reservoir can recharge, the excessive 
pressure in chamber h will cause the piston to compress 
retarding device spring 33 and move the triple valve 
parts to the position shown in Fig. 40. 

Exhaust cavity n in the slide valve 3 connects port r 
leading to the brake cylinder, with port /> to the atmos 
phere, and the brake will release ; but as the small exten- 
sion of cavity n (Fig. 40) is over port p, discharge of air 



102 WESTINGHOUSE TRIPLE VALVES. 

from the brake cylinder to the atmosphere is quite slow. 
In this way the brakes on the front end of the train 
require a longer time to release than those on the rear. 
This feature is called the "Retarded Release," and 
although the triple valves near the locomotive commence 
to release before those in the rear, as is the case with the 
old type triple valve, yet the exhaust of brake cylinder 
pressure in retarded release position is sufficiently slow 
to allow the rear brakes to release first. This permits 
of releasing the brakes on very long trains at low speeds 
without danger of a severe shock or break-in-two. 

At the same time, the back of the piston is in contact 
with the end of the slide valve bushing and, as these 
two surfaces are ground to an accurate fit, their contact 
effectually cuts off communication between chamber h 
and R through feed groove i, preventing air from feeding 
through from the brake pipe to the auxiliary reservoir by 
this path. Also port / in the slide valve registers with 
port 3' in the slide valve seat, and pressure in chamber Y 
can flow through ports y and / to chamber R and the 
auxiliary reservoir. Chamber Y is supplied with air 
under these circumstances by the check valve 15 raising 
and allowing brake pipe air to flow past it. The area of 
port / is about half that of feed grove i,'so that the rate 
at which the auxiliary reservoir will recharge is much 
less than when the triple valve is in full release position. 

As the auxiliary reservoir pressure rises, and the 
pressures on the two sides of piston 4 become nearly 
equal, retarding device spring 31 forces the piston, slide 
valve, graduating valve and retarding device stem back 
to the full release position shown in Fig. 36, when the 
remainder of the release and recharging will take place 
as previously described under "Full Release and 
Charging." 

These features of the new valve are always available, 
even when mixed in trains with the old standard, the 



WESTINGHOUSE TRIPLE VALVES. 



103 



beneficial results being in proportion to the number of 
new valves present. 

Emergency Position. Emergency position is the 
same with the <4 K" triple valve as with the old type. 
Quick action is caused by a sudden and considerable 




Fig. 41. 



reduction in the brake pipe pressure, no matter how 
caused. This fall in brake pipe pressure causes the 
difference in pressures on the two sides of piston 4 to 
increase very rapidly, so that the friction of the piston, 
slide valve and graduating valve is quickly and easily 
overcome, and they move to the left with such force that 
when the piston strikes the graduating stem it com- 
presses graduating spring 22, forcing back the stem and 
spring, until the piston seats firmly against gasket 23, 
as shown in Fig. 40. The movement of the slide valve 



104 WESTINGHOUSE TRIPLE VALVES. 

opens port t in the slide valve seat, and allows auxiliary 
reservoir pressure to flow to the top of emergency piston 
8, forcing the latter downward and opening emergency 
valve 10. The pressure in chamber Y, being instantly 
relieved, allows brake pipe air to raise the check valve 15 
and flow rapidly through chambers Y and X to the brake 
cylinder, until brake cylinder and brake pipe pressures 
equalize, when both check valve and emergency valve 
are forced to their seats by the springs in the former, 
preventing the pressure in the cylinders from escaping 
back into the brake pipe. At the same time port s 
in the slide valve registers with port r in the slide valve 
seat, and allows auxiliary reservoir pressure to flow to 
the brake cylinder. But the size of port ^ and r is such 
that very little air gets through them before the brake 
pipe pressure has stopped venting into the brake 
cylinder. 

This sudden discharge of brake pipe air into the 
brake cylinder has the same effect on the next triple 
valve as would be caused by a similar discharge of brake 
air to the atmosphere. In this way each triple valve 
applies the next, thus giving the quick and full applica- 
tion through the greater amount of brake pipe air 
admitted to the brake cylinders. The rapidity with 
which the brakes apply throughout the train is so much 
increased that in a fifty-car train it requires less than 
three seconds ; the brake cylinder pressure is also 
increased approximately twenty per cent. 

The release after an emergency is effected in exactly 
the same manner as after a service application, but 
requires a longer time, owing to the higher brake 
cylinder pressures and lower brake pipe pressures. 

To change a standard type "H" triple valve to the 
type "K," it is necessary to add the retarded release 
feature and to make the necessary changes in the 
controlling valves, body and check valve case. 



*k 




ra 



PLATE 5. LOCATION OF TRAIN AIR SIGNAL SYSTEM 



TRAIN AIR SIGNAL SYSTEM 105 

THE WESTINGHOUSE TRAIN AIR 
SIGNAL SYSTEM. 

Plate 5 shows the general arrangement of the parts 
of the train air signal system upon a locomotive, tender 
and car. This plate is not intended to show the exact 
location of the parts, but is an illustration of the general 
arrangement only. 

PRESSURE REDUCING VALVE. 

The pressure reducing valve is a valve connected to 
the main reservoir and used for supplying air to the 
signal system at a lower pressure than that in the main 
reservoir. The best results are obtained by using a 
pressure of 40 pounds, which is considered standard. 

A short, quick exhaust, or reduction, is necessary to 
cause the whistle to sound properly. The signal valve 
operates on the same principle as the quick action part 
of the triple valve, which is thrown into operation by a 
short, quick exhaust, while a longer, though a more 
gradual, reduction would cause only a service applica- 
tion. With the signal apparatus, a short, quick reduction 
will cause the whistle to respond, while a long, gradual 
reduction will not cause it to sound. 

When a slow, gradual reduction of the signal line 
pressure is made, instead of reducing the pressure in the 
signal line below that in the chamber under the dia- 
phragm, the pressure feeds from this chamber back into 
the signal line, thus removing the power that should 
operate the diaphragm or signal valve. This action is 
also assisted by the pressure reducing valve, which is 
open and feeding into the signal line at all times when 
the pressure is reduced below 40 pounds. 

Fig. 4, Plate 6, is a vertical sectional view of the 
improved signal reducing valve. The operative parts of 



io6 



TRAIN AIR SIGNAL SYSTEM. 



3 



J3, J4 




Plate 6, Figs. 1, 2, 3 and 4. 



TRAIN AIR SIGNAL SYSTEM. 107 

the reducing valve are Supply Valve 4, Supply Valve 
Spring 6, Reducing Valve Piston 7, Piston Rod 10, Dia- 
phragm 11, and Regulating Spring 13. 

Operation of the Reducing Valve. The normal 
position of the reducing valve is open as shown in Fig. 4, 
Plate 6. When the valve is in this position, air enters 
from the main reservoir at connection A ; the supply 
valve being of! its seat permits the air to pass by the seat 
of this valve into diaphragm chamber C, thence through 
port b to the signal pipe connection B. 

The signal line pressure is present at all times on the 
diaphragm, and when the desired pressure in the signal 
line is attained it exceeds the tension of regulating spring 
13 and the diaphragm is forced to its lower position, 
permitting supply valve spring 6 to seat supply valve 4, 
thus shutting of! the flow of air from the main reservoir 
to the signal line. 

The purpose of the cut-out cock is to afford a means 
of cutting off the main reservoir pressure from the 
supply valve, whenever it is necessary to remove the 
valve for any purpose, with pressure in the main 
reservoir. 

After the air has passed through the reducing valve 
it passes to the signal line throughout the entire train, 
and also to the whistle signal valve, causing it to become 
charged. 

Adjustment. The valve is adjusted by removing cap 
nut 15 and tightening up regulating nut 14, which creates 
a tension on regulating spring 13. 

SIGNAL VALVE. 

Plate 6, Fig. 1, is a sectional view of the whistle 
signal valve in its normal position. The purpose of this 
valve is to regulate the flow of air to the signal whistle. 
The two compartments A and B are separated by dia- 



108 TRAIN AIR SIGNAL SYSTEM. 

phragm 12, and diaphragm stem 10 secured thereto 
extends through bushing 9, its lower end acting as a 
valve on seat 7 of cap nut 16, above passage e. Dia- 
phragm stem 10 fits bushing 9 snugly for a short distance 
below its upper end, to where a peripheral groove is cut 
in the stem, below which it is milled in triangular form. 
Operation. While the system is being charged, air 
enters the valve from the signal line, passes through port 
d into chamber A, above the diaphragm ; also through 
port C and around piston stem 10 into chamber B, 
causing the air pressure to equalize above and below 
diaphragm 12. When a quick reduction is made in the 
signal line it causes a reduction of pressure in chamber 
A, above the diaphragm. The pressure in chamber B 
then being the greater, causes the diaphragm to raise, 
lifting signal valve 10 off its seat. The air pressure in 
chamber B passes by diaphragm stem 10 and unites with 
the air pressure passing through port C, thence through 
port c, below the valve stem, into the pipe leading to the 
whistle, which causes a blast. The same reduction of 
signal line pressure which causes the signal valve to 
operate also causes the reducing valve to open, 
which permits main reservoir pressure to flow into 
the signal line, restoring the pressure. This raises the 
signal line pressure and also causes pressure to be raised 
in chamber A, above the diaphragm, moving it to its 
lower position, as shown in Fig. 1. Equilibrium of 
pressure quickly occurs in chamber's A and B, and the 
valve at the lower end of stem 10 returns to its seat. 

CAR DISCHARGE VALVE. 

The car discharge valve is usually located above the 
door outside of the car, and opposite the opening through 
which the signal cord passes. A branch pipe extends 
from the main signal pipe to the car discharge valve, and 



TRA1X AIR SIGNAL SYSTEM. 109 

in this pipe is placed a one-half-inch cock, by means of 
which the valve on the car may be cut out when desired. 

The pressure in the signal line is reduced by means 
of the car discharge valve, and can be operated from any 
part of the car by means of a cord known as the whistle 
cord. 

Operative Parts. The operative parts of the car dis- 
charge valve are the Discharge ValVe 3, Discharge Valve 
Spring 4, and Discharge Valve Handle 5. The normal 
position of this valve is closed, as shown in Fig. 2, 
Plate 6. 

Operation. The valve is operated by means of valve 
handle 5, which is in the form of a lever. By moving 
this lever in either direction it forces discharge valve 3 
from its seat, which compresses discharge valve spring 4, 
thus permitting air pressure to escape from the signal 
line to the atmosphere. 

When operating the air whistle signal, the car dis- 
charge valve should be held open for at least one second 
in order to produce a proper blast of the whistle. 

An intermission of about three seconds should be 
allowed between blasts on trains of five cars or less, and 
one second should be added for each additional car in 
the train. The spacing of the blasts is necessary in order 
to give the air pressure in the signal valve sufficient time 
to equalize above and below the diaphragm of the signal 
valve between each blast of the whistle (Fig. 1, Plate 6). 

Overcharging Signal Line. Overcharging of the air 
signal line is usually due to there being a direct opening 
between the signal line and the main reservoir, which 
will allow air to flow from the signal line to the main 
reservoir each time the main reservoir pressure is 
reduced. This causes a reduction of signal line pressure 
at the signal valve, which, if the opening through the 
reducing valve is large enough and the main reservoir 



no TRAIN AIR SIGNAL SYSTEM. 

pressure is reduced sufficiently fast, will open the signal 
valve, causing the whistle to sound. 

When the signal line is overcharged it can be 
detected from the train by a strong discharge of air from 
the discharge valve, and on the engine by the signal 
whistle, as the bell of the whistle is adjusted for a 
pressure of 40 pounds instead of 90 or 120. 

Adjusting the Whistle. The whistle (Fig. 3, Plate 6) 
can be adjusted by loosening up the lock nut and 
unscrewing or screwing up the bell, occasionally making 
a reduction in the signal line and noting whether the 
proper sound is produced. 

Testing Signal Line Pressure. A test of the pressure 
in the signal line can be made from the engine without 
the use of a test gauge by shutting off the air pump, 
gradually reducing the main reservoir pressure and 
watching the red hand of the gauge. When the whistle 
blows the air gauge will indicate the pressure in the 
signal line. 

DEFECTS OF THE AIR SIGNAL SYSTEM. 

Failing to Charge. If the signal line fails to charge it 
should first be noted that it is cut in between the tank 
and the first car, that all angle cocks on the train are 
open, except the one on the rear end of the train, which 
should be closed, and that the reducing valve is cut in 
and properly adjusted. If the trouble still continues it 
may be due to the choke in the reducing valve becoming 
stopped up so that no air can pass through, a collapsed 
hose lining which would block the passage, or, in cold 
weather, the signal line between the tender and engine 
may be frozen. 

Failure of Whistle to Sound. If the signal line is 
properly charged and an exhaust occurs at the discharge 
valve when the whistle cord is pulled properly, but the 



TRAIN AIR SIGNAL SYSTEM. in 

whistle fails to give a blast, the trouble may be due to 
the strainer in the tee pipe connection of the branch pipe 
to the signal line being partly stopped up ; port d of the 
signal valve being stopped up so that no air can enter 
to charge it ; stem 10 of the signal valve becoming worn 
sufficiently loose in bushing 9 to allow the pressure in 
chamber B to reduce as rapidly as that in chamber A ; 
the signal valve diaphragm becoming baggy or having 
a hole in it ; the passage in bushing 7 becoming stopped 
up, or stem 10 fitting too tightly in bushing, not allowing 
chamber B to charge ; the bell of the signal whistle not 
being properly adjusted, or its bowl filled with dirt; the 
whistle being located so that the wind blowing across 
the bowl from an open cab window prevents it from 
sounding, or the choke in the reducing valve being too 
large, allowing the signal line to be charged as fast as 
the reduction is being made. 

One long blast. If the air whistle gives one long blast 
it may be due to the reductions being made too close 
together, or diaphragm stem 10 working stiffly in bush- 
ing 9, in which event the passage at e would remain open 
until a sufficient difference of pressure exists in chambers 
A and B to force stem 10 to its seat. 

Two or More Blasts. If the air whistle gives two or 
more blasts each time the cord is pulled the trouble is 
due to a stiff diaphragm, or diaphragm stem 10 fitting too 
loosely in bushing 9, in which event the reduction in 
chamber A would allow chamber B to respond too 
quickly and reduce its pressure below that in chamber A, 
causing chamber A pressure to force stem 10 to its seat, 
and this would be repeated several times during one 
reduction of chamber A pressure. 

Whistle Sounding When Brakes are Released. If the 
air whistle gives a blast each time the brakes are released 



112 TRAIN AIR SIGNAL SYSTEM. 

it indicates that the signal line pressure is charged up 
to that in the main reservoir, which is caused by the 
tension of the regulating spring being too great, the 
supply valve of the reducing valve being held from its 
seat, or a leak by the diaphragm, and the opening in the 
spring casing stopped up. 



CYLINDER AND AUXILIARY RESERVOIR. 113 

COMBINED FREIGHT GAR CYLINDER 

AND AUXILIARY RESERVOIR WITH 

TRIPLE VALVE ATTACHED. 

The combined freight car cylinder and reservoir (Fig. 
43) is the usual form of equipment applied to freight 
cars. On a part of the cars in use the cylinders and 
auxiliary reservoirs are separated, but the triple valve, 
auxiliary reservoir and brake cylinder are the same 
in both cases. The auxiliary reservoir 10 is simply a 
hollow shell for the purpose of storing air for use in the 
brake cylinder upon the same car. Pipe b provides com- 
munication between the triple valve and the brake 
cylinder. Upon passenger cars this pipe does not pass 
through the auxiliary reservoir, but the operation of the 
brake is the same ; it is simply a different arrangement 
of the same parts. 

List of Parts and Their Purposes. 2 is the brake 
cylinder ; 3 is the piston and sleeve in which the push rod 
connected with the system of brake levers is inserted ; 
4 is the non-pressure cylinder head ; 9 is the release 
spring, which forces piston 3 to release position when the 
air pressure is released from the pressure end of the 
cylinder ; 7 is a packing leather, which is pressed against 
the cylinder wall to prevent air from escaping past the 
piston ; 8 is a round spring packing expander, which 
serves to hold the flange of the packing leather against 
the walls of the cylinder; 6 is the follower plate, which, 
by means of studs and nuts 5, clamps the packing leather 
to the piston, and a is a small groove, indicated by dotted 
lines in the wall of the cylinder, called the leakage 
groove. 

If the exhaust port on the slide valve of the triple 
valve should in any manner become obstructed, when it 



114 CYLINDER AND AUXILIARY RESERVOIR. 




Tig. 42. 



CYLINDER AND AUXILIARY RESERVOIR. 115 

is not desired to have the brakes applied, a slight flow of 
air into the brake cylinder will, instead of forcing the 
piston out, escape through leakage groove a to the 
atmosphere at the non-pressure end of the cylinder. 

Valve 17, usually placed on the upper side of the 
auxiliary reservoir, is known as the release valve. A 
rod extends from the arms of this valve to each side of 
the car. Pulling either rod unseats the valve and dis- 
charges air from the reservoir for .the purpose of releasing 
the brake. 

Sizes of Brake Cylinders. Brake cylinders with a 
diameter of 6, 8, 10, 12, 14 and 16 inches, and of various 
lengths, are used on cars of various capacities. The size 
of the brake cylinder is determined by the total light 
weight of the car resting on the rails. 

Sizes of Reservoirs. A reservoir 10x24 inches is 
required with 8-inch cylinders on passenger cars ; 10-inch 
cylinders are used with I2x33~inch reservoirs on pas- 

f 







Westinghouse Passenger Car Brake Cylinder and Triple Valve. 
Fig. 44. 



senger equipment ; 12-inch cylinders are used with 14x33- 
inch reservoirs, passenger equipment ; 14-inch cylinders 
with i6x33~inch reservoirs with engine, tender and 



n6 AUTOMATIC SLACK ADJUSTER 

passenger equipment, while with a 16-inch cylinder on 
passenger equipment a reservoir 16x42 inches is used. 
For freight car equipment, on which cylinders 6, 8 and 10 
inches in diameter are used, a standard cast-iron reservoir 
of different sizes adapted to each size of cylinder must 
be used. 

Fig. 44 shows a sectional view of the passenger car 
brake cylinder with special head and triple valve 
attached to it, in the same manner in which the triple is 
connected to the auxiliary on freight equipment. 

DEFECTS OF THE BRAKE CYLINDER. 

Any leakage from the brake cylinder will cause the 
brake to release. This is usually caused by the packing- 
leather becoming cut or very dry, and not forming an air- 
tight joint between the piston and the cylinder wall. 

If the expanding ring is not placed in its proper position 
the packing leather will not be held against the cylinder 
wall, thus permitting a leakage. In some cases it will also 
bind the piston, preventing it from returning to release 
position after the pressure has been exhausted. ' 

A broken or weak piston release spring will fail to force 
the piston to its normal or release position after the pressure 
has been exhausted from the cylinder. 

If the leakage groove becomes stopped up and the 
exhaust port is obstructed, it will possibly cause the brake to 
set slowly, if a leak exists in the brake pipe, as the air that 
is admitted to the brake cylinder cannot escape past the 
piston. 

AUTOMATIC SLACK ADJUSTER. 

The automatic slack adjuster is a simple mechanism, by 
means of which a predetermined piston travel is constantly 
maintained, compelling the brakes of each car to do their 
full amount of work, thus securing from the brakes their 



AUTOMATIC SLACK ADJUSTER. 117 




Plate 7, Fig. 1. 



Ji8 AUTOMATIC SLACK ADJUSTER. 

highest efficiency, eliminating the danger of causing flat 
wheels, which is likely to occur with a wide range of piston 
travel. This device establishes the running piston travel, 
that is, the piston travel when the brakes are applied while 
the car is in motion, and, since this is the time during which 
the brakes perform their work, the running travel is the 
important one. Hand adjustment of brakes necessarily 
relies upon the standing travel, and it is only coarsely graded 
by the spacing of the holes in the dead lever guide. 

Operation. The slack adjuster is shown on Plate 7, 
Figs. 1, 2 and 3. The brake cylinder piston acts as a valve 
to control the admission and release of brake cylinder 
pressure to and from pipe b (Fig. 1), through port a in the 
cylinder, this being so located that when the piston uncovers 
port a, brake cylinder air flows through pipe b into slack 
adjuster cylinder 2, where the small piston 19 (Fig. 2) is 
forced outward, compressing spring 21. Attached to piston 
stem 23 is a pawl extending into casing 24, which engages 
ratchet wheel 27, mounted within casing 24, upon screw 4 
(Fig. 1). When the brake is released, and the brake cylin- 
der piston returns to its normal position, the air pressure in 
cylinder 2 escapes to the atmosphere through pipe b, port a 
and the non-pressure head of the brake cylinder, thus per- 
mitting spring 21 (Fig. 2) to force the small piston to its 
normal position. 

In so doing, the pawl turns the ratchet wheel upon screw 
4 and thereby draws lever 5 slightly in the direction of the 
slack adjuster cylinder, thus shortening the piston travel and 
forcing the brake shoe nearer the wheels. As the pawl is 
drawn back to its normal position a lug on the lower side 
strikes projection a (Fig. 3) on the cylinder, thus raising 
the outer end of the pawl, disengaging it from the ratchet 
wheel, and permitting the screw to be turned by hand if 
desired. The screw mechanism is so proportioned that the 
piston travel is reduced only about 1/32-inch by each 



AUTOMATIC SLACK ADJUSTER. 



119 



operation, which removes the danger of unduly taking up 
false travel. 

Improper Adjustment. If the piston travel is found 
to be too long when the small pipe leading to the adjuster 
cylinder is free from obstruction, and the packing leather 




APPLIED 
Fig. 2. 



Plate 7. 



RELEASED 
Fig. 3. 



in the adjuster cylinder is free from leakage, it is more than 
probable that the slack has been taken up through an appli- 
cation, with only partial release of the hand brakes, and 
full release occurring only after the shoes have had time to 



120 AUTOMATIC SLACK ADJUSTER. 

wear. If the piston travel becomes too short, it will be 
found that some of the slack in the brake rigging has 
been taken up by the hand brake where the two work in 
opposition, or the dead levers have beemmoved. 

Purpose of the Slack Adjuster. The purpose of the 
slack adjuster is to maintain a predetermined piston travel, 
as by constant wear the brake shoes become thinner, which 
causes the brake piston to travel farther and results in 
reducing the brake cylinder pressure and the holding power 
of the brake. 

The automatic adjuster regulates the piston to its proper 
running or working travel, regardless of the length of 
travel, or whether the car has high or low leverage. There- 
fore, if all cars in a train were equipped with automatic 
adjusters, the travel of all pistons would be uniform when 
the brakes were set to slow down or stop the train, the 
same brake cylinder pressure would be had on all cars at 
each and every reduction, and all cars in the train would 
develop equal braking power. 

As the work of the adjuster is based on running travel, 
the travel of the pistons will be uniform, but the standing 
travel of the pistons will not necessarily be uniform on all 
cars in the train. 



PRESSURE RETAINING VALVES. 



121 



PRESSURE RETAINING VALVES. 

STANDARD PRESSURE RETAINING VALVE. 

The standard type of pressure retaining valve, used on 
6, 8 and io-inch cylinders, is shown on Plate 8, Figs. I and 2. 
It consists of weighted valve 4, enclosed in casing 3, and 
seating in passage b ; this valve is screwed on to the farther 
end of a pipe leading to the exhaust port of the triple valve. 





. Fig. 1. Plate 8. Fig. 2. 

Operation. When the handle of the pressure retain- 
ing valve is turned downward, pointing perpendicularly 
(Fig. 1), the pressure escapes from the brake cylinder 
through the retaining valve pipe to the retaining valve, where 
it escapes freely to the atmosphere, entering the retaining 
valve at X, and passing through ports b and c to the atmos- 
phere. In this position the valve is not in operation and 
has no duty to perform. 



122 PRESSURE RETAINING VALVES. 

When the handle of the retaining valve is turned upward, 
pointing horizontally, the direct outlet from the retaining 
valve pipe is closed. As shown in Fig. 2, the air is dis- 
charged from the brake cylinder through the triple valve, 
retaining valve pipe and ports b, a and b, as before. Port c 
now being closed, the air pressure must lift weighted valye 4 
and pass to. the atmosphere through the restricted port d. 
All pressure over 15 pounds will hold .the valve from its 
seat and escape through a small port in the cage. This 
valve is so proportioned that it will seat only when 15 
pounds or less pressure is exerted upon it. Thus the last 
15 pounds is retained in the brake cylinder, which is sufficient 
to steady the train while the auxiliary reservoirs are being 
recharged. 

The retaining valve not only holds a braking power of 
15 pounds in the cylinders, but the passageway out of the 
casing to the atmosphere is restricted to such an extent that 
a considerable time is consumed in discharging the brake 
cylinder pressure through the small port. This renders the 
release of the brake much slower and exerts a retarding 
effect, which gives more time for the recharging of the 
auxiliary reservoir. 

Difference in Sizes of Port d. Port d is not the same 
size in all retaining valves. It is 1/16-inch in the retaining 
valves used with 6, 8 and 10-inch cylinders, and 1 /8-inch in 
those used with 12, 14 and 16-inch cylinders. These port 
sizes give a restriction which requires from 30 to 60 seconds 
for the cylinder pressure to escape down to the amount 
limited by the weighted valve. The figures given cover the 
standard retaining valve. This has been found by repeated 
tests to be the standard pressure for cars in interchange 
service, and gives good results in braking on long grades 
without excessive heating of wheels. In mountain districts 
there are other types of retaining valves used to some extent, 



PRESSURE RETAINING VALVES. 123 

but they are not considered standard, and are not in general 
use. 

Advantages of the Retainer. The retaining valve also 
permits a much safer handling of trains, the maintenance 
of a more uniform rate of speed down heavy grades and a 
saving of air pressure. It gives an increased cylinder 
pressure and a higher braking power with a lower consump- 
tion of air pressure, and in addition permits a greater 
reserve in stopping power for emergencies. 

The retaining valve cannot be used to advantage in 
driver brake operation. This is due to the fact that driving 
brake packing generally leaks and the various connections 
in the brake cylinder pipe frequently become loose, causing 
a leakage. With these avenues of escape for pressure, the 
retaining valve is unable to perform its functions. The 
driver brake retaining valve has almost entirely given way 
to the combined automatic and straight air brake, which 
overcomes the leakage difficulties. 

HIGH AND LOW PRESSURE RETAINING 

VALVE. 

The great value of the standard pressure retaining valve 
in the safe handling of trains on heavy grades has been 
demonstrated repeatedly. The growing severity of modern 
breaking conditions, as a result of which average loads of 
73 tons per brake, on trains of 25 or more cars over grades 
of 200 feet to the mile, are frequently encountered, has 
brought about several methods of increasing the certainty 
of controlling such heavily loaded trains ; one by raising the 
brake pipe pressure from 70 to 90 pounds, which gives a 
greater reserve for reapplication after release ; another by 
increasing the percentage of braking power, and using the 
standard pressure retaining valve ; a third by the introduction 
of a special pressure retaining valve. 



124 PRESSURE RETAINING VALVES. 

The standard retaining valve is designed to maintain a 
brake cylinder pressure of 15 pounds while the auxiliary 
reservoirs are being recharged, and ordinarily this pressure 
is sufficient. Under extreme conditions, however, it has 
proved desirable to increase the amount of pressure retained 
in the brake cylinders, during the recharge of the auxiliary 
reservoirs, to 30 and sometimes 50 pounds. This condition 
has been met by the manufacture of a high and low pressure 
retaining valve which fully meets these requirements. It 
will be understood that this valve is only an accessory to the 
regular brake apparatus and is not intended to replace the 
more important factors required in heavy freight service, 
such as adequate braking power, proper size cylinders, suit- 
able leverage, and the exercise of good judgment in the 
maintenance and operation of the brakes. 

Operation. This new retaining valve is very similar 
to the standard type in general design and location, but 
is modified as indicated on Plate 9, Figs. 1 and 2. The 
main difference consists in the addition of a cylindrical 
weight 10, which surrounds the usual weight and is 
lifted by it, whenever valve handle 5 is manipulated to 
retain 30 pounds. When handle 5 is placed in a hori- 
zontal position, one of two eccentric lugs on it raises pin 
9 and also outer weight 10, the latter to the top of its 
movement. During such time inner weight 4 alone 
retains the pressure. 

If the handle is placed in the intermediate position 
marked 'nigh pressure" (Fig. 2), neither eccentric lug' 
nor handle 5 touches lifting pin 9, and consequently 
outside weight 10 rests upon the top of inner weight 4, 
and the air pressure must raise both weights before it 
can escape to the atmosphere. When the handle is 
placed vertically, as shown in Fig. 1, the air passes 
directly to the atmosphere, thus cutting out the retaining 
valve, while at the same time the other eccentric lug on 



PRESSURE RETAINING VALVES. 



125 



the handle raises the lifting pin and outside weight, so 
that the small weight alone rests on the valve seat. 

Positions of the Handle. The exhaust and low pres- 
sure positions of this retaining valve are similar to those 
of the standard retaining valve. Thus, when cars 




Fig. 1 



Plate 9. 



equipped with this valve are running in localities free 
from heavy grades, where the train crews are familiar 
only with the standard valve, they cannot by mistake 
place the handle in the high pressure position. The 
letters "H. P." and "L. P.," indicating respectively high 
pressure and low pressure, are cast on the body of the 



126 PRESSURE RETAINING VALVES. 

valve, so as to assist still further in indicating the 
positions of the valve handle. 

The development of this device was coincident with 
a series of interesting and valuable tests made by a lead- 
ing railway company with a view of determining what 
is actually required to hold heavy trains under perfect 
control when descending heavy grades, through using 
higher air pressure, special pressure retaining valves, 
water brake on the locomotive, and the combined auto- 
matic and straight air brake equipment on the engine 
and tender. The results of these tests indicate that to 
control such trains suitably, the minimum brake pipe and 
auxiliary reservoir pressures should not fall below 70 
pounds, in order to give sufficient reserve braking power 
to stop the train on a heavy grade in cases of emergency. 

This at once necessitates an increase in air pressure 
throughout the system, as standard maximum brake 
pipe pressure is 70 pounds. Although this increase was 
provided, this change alone did not suffice to control the 
trains, and a special high and low pressure retaining 
valve was introduced, which was designed to retain a 
cylinder pressure of 25 pounds for use upon grades of 
2^% or less, and 50 pounds for grades approximately 
4%. It should be stated, however, that the conditions 
surrounding these tests were extreme, and that the high 
and low pressure retaining valves furnished as standard 
are proportioned for 15 and 30 pounds respectively. 

DEFECTS OF THE RETAINER. 

If there is a steady leakage of pressure at the retain- 
ing valve when the brake is released, the trouble will be 
found in the triple valve. 

If the retaining valve handle has been turned upward 
in a horizontal position, the brakes then released, and 
after a few moments the handle is turned downward 



PRESSURE RETAINING VALVES. 127 

and no air escapes, the trouble is not in the retaining 
valve, but is caused by a leaky joint or connection in the 
pipe, or by the valve being held from its seat by dirt. If 
there is no leakage it indicates a leak at the brake 
cylinder packing. 

If air fails to pass through the retaining valve, with 
the handle turned down and the brakes remain set, the 
trouble should be looked for at the exhaust port, which 
may have been stopped up by an accumulation of dirt. 



128 AUTOMATIC AND STRAIGHT AIR. 

COMBINED AUTOMATIC AND 

STRAIGHT AIR LOCOMOTIVE 

BRAKE EQUIPMENT. 

The combined automatic and straight air engine and 
tender brake, shown diagrammatically on Fig. 48, con- 
sists of the standard automatic arrangement employed 
on engine and tender, with the addition of a straight air 
brake valve, reducing valve, tw T o double check valves, 
two safety yalves, a straight air gauge, special hose and 
necessary piping, which permits the use of straight air 
on the engine and tender brakes without interfering with 
their automatic action when the automatic brake valve is 
used, both being cut in at all times. The many impor- 
tant advantages of an independent engine and tender 
brake are thus obtained, while preserving at all times 
every function of the automatic on these and the train 
brakes. Without this latter requisite no independent 
brake can be considered either safe or economical. 

The straight air is used for passenger, freight and 
switching locomotives. The parts for the engine are 
known as schedule S-W-A and for the tender as schedule 
S-W-B. 

General Arrangement. Fig. 49 shows the general 
arrangement of the combined apparatus and the posi- 
tions of the brake valves and double check valves when 
the automatic brake is applied. , Fig. 50 shows the corre- 
sponding positions when the straight air brake is applied. 
Connection with the automatic is made at three points, 
viz. : to the main reservoir and the brake cylinder pipes 
of the driver and tender brakes. 

The straight air supply is taken from the main reser- 
voir pipe between the main reservoir and the automatic 
brake valve so as to insure clean, dry air. Before reach- 



AUTOMATIC AND STRAIGHT AIR. 




129 



Fig. 48. 



130 AUTOMATIC AND STRAIGHT AIR. 

ing the straight air brake valve it must pass through the 
reducing valve, which is set at 45 pounds, and consists of 
a standard slide valve feed valve as used on the automatic 
brake valve, attached to a special pipe connection made 
for that purpose. This reducing valve should always be 
located in the cab, preferably at a point where it will be 
prevented from freezing in cold weather. 

The double check valve on the engine and tender is 
connected as shown. The air must pass through this 
valve when either applying or releasing the brakes with 
the straight air or automatic equipment. 

The two side openings of the double check valve 
(Fig. 56) are the brake cylinder connections, joined by 
a cored passageway. The safety valve on the tender 
may be screwed into one of the cylinder connections of 
the double check valve, as indicated in the cuts, or in the 
pipe between the double check valve and the cylinder. 
On the engine, one brake cylinder should be connected 
to each of the double check valve cylinder connections, 
and the safety valve in either driver brake cylinder pipe- 
Each safety valve should be adjusted to open at 53 
pounds. It should be in direct communication with 
brake cylinder pressure, whether the automatic or 
straight air is used, and should be placed vertically to 
prevent dirt and water from accumulating inside of the 
valve. 

As the straight air should never give over 45 pounds 
cylinder pressure, and the automatic not over 50 pounds, 
a correctly adjusted safety valve will never operate 
unless an improper condition exists, but when it does 
exist it will guard against a dangerously high cylinder 
pressure. 

The grade cocks C and D with their pipes are for use 
only on locomotives operating over heavy mountain 
grades. They are to be opened only when descending 



AUTOMATIC AND STRAIGHT AIR. 



131 




132 AUTOMATIC AND STRAIGHT AIR. 




H 




z 




w 




s 




Ph 




IH 




D 




ff 




w 




55 




l-l 




o 




fc 




w 








o 


M 


M 


|4 


w 


P4 


tf 


Pk 


fa 


< 


Q 
W 


to 


% 


W 


m 


< 
Pi 


o 
a 


CO 


to 


Pi 


O 


< 


fc 


H 


o 


ffl 


H 


o 


< 


3 

Pi 

02 


•4 








a 




M 




H 




« 




s 




s 




2 




tt 




< 





Fig. 50. 



AUTOMATIC AND STRAIGHT AIR. 133 

very long grades and should be closed immediately upon 
reaching the foot of the grade. Cock C should be placed 
adjacent to the gangway so that it can be operated when 
running, and cock D should be placed near the engine- 
man's seat. When descending heavy grades both cocks 
are left open. The driver and tender auxiliary reservoirs 
are recharged simultaneously with those of the train, 
but automatic application is prevented on the brakes of 
the former, thus permitting the greatest use practicable, 
without danger of loosening the tires of the tender and 
engine, when recharging the train brakes. A and B, 
Fig. 49, indicate the gauge connections, a gauge for 
straight air being absolutely necessary for satisfactory 
service. The gauge should be connected so as to show 
the brake cylinder pressure in the automatic as well as 
the straight air applications, such connections being indi- 
cated by B. For attaching a test gauge, a tee should be 
put in the pipe from the straight air brake valve to the 
double check valve. It should be placed close to the 
former so that by taking out the ^-inch plug in its side 
opening and connecting a gauge, the latter can readily 
be seen while operating the brake valve and adjusting 
the reducing valve. 



REDUCING VALVE PIPE BRACKET. 

Fig. 51 shows the special pipe bracket to which a 
standard slide valve feed, valve, acting as a reducing 
valve for the straight air, is connected. Inlet port A and 
outlet port B come opposite the similar ports in the feed 
valve. The arrow shows the direction of the flow of air 
across the dividing wall. 

The B-3 reducing valve, shown in Figs. 24 and 25, is 
the well-known feed valve that has been used for many 



134 



AUTOMATIC AND STRAIGHT AIR. 



years in connection with the G-6 brake valve, and this 
valve is also used and attached to a pipe bracket. 

To adjust the valve, the cap nut on the end of the 
spring - box should be removed, which will expose the 



FROM MAIN 
RESERVOIR 



MR 



W"'i'"l" 



Z> 



'5 PIPE TAP 






£> 



V_ 



Sf". ii ''Jul"! 

'(' |".H,tt, | ll'|.i 

n'lVri 1 "' 1 '!'! 

ii'i'i'i'i'i'i'iVi 
jilkW&fti 




1 £f^ 



TO STRAIGHT Alft 
BRAKE VALVE 



BV 



3", 



PIPE TAP 



Fig. 51. 

adjusting nut by which the adjustment is made. It is 
called a reducing valve when used with the straight air 
brake valve, simply to distinguish it from the feed valve 
supplying the automatic brake. 



STRAIGHT AIR BRAKE VALVE. 

Parts and Their Uses. Fig. 52 is a sectional view of 
the straight air brake valve parallel with shaft 2, operated 
by handle 4, which opens application valve 8 or release 
valve 9. As indicated by b, b' and b" , the space above 
admission valve 8 is connected with that below exhaust 
valve 9. The leather gasket 6 makes the joint at the shaft 
collar. 

Operation. Fig 53 is a sectional view across the 
shaft at application valve 8, showing the connection MR by 
which main reservoir pressure, reduced to 45 pounds, reaches 
the lower side of valve 8, through cavity a. 

Fig. 54 is a similar section across the shaft at exhaust 
valve 9, showing the cavity b below this valve, the brake 
pipe connecting at DCV, leading to the double check valves 



AUTOMATIC AND STRAIGHT AIR. 



135 



and past them to the brake cylinders; also passageway c 
leading from the above release valve 9 through the exhaust 
opening to the atmosphere. Fig. 55 is a horizontal section 
showing the relative positions of the valves and connections. 
Shaft 2 is slotted out to the middle at two points, and 




MR TDCV 

FROM MAIN RESERVOIR ™, °° U ^ f v^ne^ 
AND SLIDE VALVE FEED VALVE VAt - Vfc ANO CTUND5RI 

Fig. 52. 

valves 8 and 9 are just enough off the shaft center line so 
that the stem of each valve will end just beneath the flanged 
portion of the steel tapped piece riveted into each of the shaft 



136 AUTOMATIC AND STRAIGHT AIR. 



r\ 




FROM MAIN RESERVOIR. 

M.R 



Fig. 53. 



AUTOMATIC AND STRAIGHT AIR. 



137 



slots. As shown by the sectional view (Fig. 54) of valve 9, 
these valves are fitted with leather seats and have steel caps 
to reduce the wear. 

In Fig. 53, handle 4 is shown in lap position, valves 8 




/EX 
EXHAUST 



7dcv 

FROM DOUBLE CHECK 
VALVE AND CYLINDER 



Fig. 54. 



and 9 being held to their seats by springs 10 and 11, and 
any air pressure that may be below them. This position 
embodies the space that can be covered by the handle move- 



138 



AUTOMATIC AND STRAIGHT AIR. 



ment without unseating either valve. Moving handle 4 
(Fig. 52) to the right unseats application valve 8 and allows 
main reservoir pressure to flow from chamber a, past valve 8 
to chamber b, thence through passage b' to b" , bringing it 
under release valve 9 and in communication with the pipe at 




SECTION AT A-B 



DOUBLE CHECK 
VALVE AND 
CYLIND£H 



Fig. 55. 

DCV, by which it is carried to the double check valves and, 
past them, to the cylinders, applying the brakes. Moving 
handle 4 in the reverse direction (Fig. 54) will permit 
application valve 8 to seat, unseating release valve 9 and 
releasing the brakes. 



NO. 2 DOUBLE CHECK VALVE. 

Figs. 56 and 57 show the double check valve in section, 
the several connections being indicated thereon. Between 
the two seats, b and d, is piston valve 10, which has a leather 
face on each end. The piston valve is shorter than the 
distance between its two seats, and the bushing in which it 
works has two series of ports, c and c'. When the piston 



AUTOMATIC AND STRAIGHT AIR. 



139 



is against seat b, as shown in Fig. 56, port c opens a free 
passage for the air between the straight air brake valve and 
the brake cylinder. The opening leading to the triple valve, 
which is now in* release position, is closed so that no leakage 
can occur. 

Release Position. When the straight air brake valve 
is in release position (its normal position when not in use), 
and an automatic application is made, the air from the triple 
valve upon entering the double check valve will force the 



TO BRAKE CYLINDER 




SAFETY VALVE OR ONE CYLINDER 
WITH DRIVER BRAKE 



Fig. 56. 

piston valve to the right against seat d (Fig. 57), thus pre- 
venting any escape of pressure at the straight air brake valve, 
and opening ports c' so that air can flow into the brake 
cylinder, returning the same way when released. 

Position of Double Check Valve. The double check 
valve must be placed in a horizontal position so that its 
piston valve will not be moved except by air pressure. The 
use of either automatic or straight air will cause its piston 
valve to move automatically to the proper position. 



140 



AUTOMATIC AND STRAIGHT AIR. 



Grade Bleed Cocks. As grade bleed cocks are con- 
nected between the driver and tender triple valves and their 
double check valves, when left open they will prevent auto- 



TO bnAKE CYLINDER 




SAFETY VALVE OR ONE CYLINDER. 
WITH DRIVER BRAKE 



Fig. 57. 

matic action on these brakes by allowing the air to pass 
directly to the atmosphere instead of through the double 
check valves. 



TYPE "E" SAFETY VALVE. 

Operation. Fig. 58 shows the type "E" safety valve. 
Valve 4 is held to its seat by the compression of the spring 
between stem 5 and adjusting nut 7. When the pressure 
below valve 4 is in excess of the tension of the spring, the 
valve raises, being guided in its movements by the brass 
bushing in body 2. Ports are drilled in this bushing, one 
outward through the body to the atmosphere, and the other 
upward to the spring chamber. Although only one of each 
of these ports is shown in the cut, there are in reality eight 



AUTOMATIC AND STRAIGHT AIR. 



141 



of the first and two of the second. As the valve moves 
upward, its lift is determined by stem 5 striking lock nut 3, 
which closes the vertical ports connecting the valve and 
spring chambers and opens the ports to the atmosphere. As 
the area of the valve is large, and there are a number of these 
ports leading to the atmosphere, a large volume of air will 




Fig. 58. 

be released quickly. As the air pressure below valve 4 
decreases, and the tension of the spring forces the stem and 
valve downward, the valve gradually closes the ports to the 
atmosphere and opens those between the valve and spring 
chambers. The exhaust air then has access to the spring 
chamber. 

Although the spring chamber is connected with the 
atmosphere by two small ports or holes, drilled through 
body 2, the air entering from the valve chamber through 



142 AUTOMATIC AND STRAIGHT AIR. 

the vertical ports in the bushing will not flow to the atmos- 
phere unless a pressure head is realized in the spring 
chamber. This pressure, added to that of the spring, causes 
the valve to close quickly with a "pop" action, which insures 
its seating firmly and completely. 

This action, together with the large quantity of air 
passing through the valve when discharging, keeps the valve 
in its seat clean and in good condition, thus prolonging its 
life and insuring its proper operation and reliability. Also 
the difference between the opening and closing pressures is 
minimized, and the sensitiveness of the valve in operation 
greatly increased, causing it to respond to very slight differ- 
ences in pressure, and to close promptly when the pressure 
is reached for which it is regulated. 

Reducing and Safety Valve Adjustments. If the 
straight air reducing valve is set at too low a pressure, the 
brakes will not hold well, but the automatic action will not 
be affected. The adjustment of the reducing valve should 
not be changed without the use of a gauge which is accurate. 

Any pressure above 45 pounds will give more brake 
power than is desired, and if it is above 53 pounds it will 
cause the safety valve to blow and waste air with a full 
application of the brakes. 

Safety valves that are set too low or that leak when 
seated will also cause a waste of air. If the safety valves 
are set too high they will not prevent an excessive cylinder 
pressure, and in cases where the reducing valve is adjusted 
too high or is out of order, or if the automatic is applied 
with the straight air set, the wheels are liable to slide. 

Unless the straight air has a separate gauge, or one that 
can be temporarily attached, as indicated at A and B (Fig. 
49), the best plan, when cleaning and adjusting are required, 
is to replace the safety valves and the feed valve part of the 
reducing valve with others that have been put in good order. 

The safety valves should be set so that they will just 



AUTOMATIC AND STRAIGHT AIR. 143 

commence to blow with a pressure of 53 pounds, after which 
the reducing valves should be regulated to act at 45 pounds 
pressure. 

One of the best methods of adjusting the reducing valve 
when the air gauge, is known to be correct is to clean and 
lubricate the slide valve feed valve on the brake valve, and 
adjust it at 45 pounds. All the air pressure should then be 
reduced, and this reducing valve exchanged with that on 
the straight air. The latter should then be cleaned and 
lubricated, and adjusted to the standard brake pipe pressure. 

ADVANTAGES OF THE COMBINED AUTOMATIC 
AND STRAIGHT AIR BRAKES. 

The purposes of the combined automatic and straight air 
brakes are as follows : 

First. — To quicken the work of switching and reduce the 
incident damage to lading and equipment. 

With the straight air brake drawing its supply of air 
from the main reservoir, the holding power and possible 
speed of application never varies from one application to 
another ; the release, if so desired, is practically instan- 
taneous. The holding power of the brakes can be increased 
or diminished either quickly or slowly as desired, and the 
maximum pressure is not affected by ordinary leakage, or 
by long piston travel, unless the latter is sufficiently long to 
permit of the piston striking the head. With the straight 
air, unlike the automatic, it is possible to make a partial 
release, and this may be made with any desired rapidity. 
Application immediately after release is never delayed as 
with the automatic, when there is an overcharged brake pipe 
and a reduced auxiliary reservoir pressure. The driver and 
tender brake cylinders being connected when using straight 
air, the distribution of brake power is not affected by vari- 
ation in piston travel or cylinder leakage, and there is 
therefore less danger of wheel sliding. 



144 AUTOMATIC AND STRAIGHT AIR. 

Second. — To permit the brakes on long trains to be 
released without danger of slack running out suddenly and 
breaking the train in two, which is otherwise liable to occur 
at slow speeds. Allowing the train brakes to be released 
with safety at slow speeds prevents the loss of time and 
occasional damage incident to starting the train in an 
unfavorable location, at which a stop is necessitated, by 
reason of the engine not being equipped with straight air 
brakes. 

Third. — To prevent changes of grade, sags, or curvature 
of tracks from running the slack of long trains in or out so 
suddenly as to cause severe shocks and train separation. 

Fourth. — To slow up or stop trains when the braking 
power required is not heavy. This reduces pump labor, 
wheel sliding and the break-in-twos incident to an endeavor 
to start long trains with brake shoes dragging, or stuck 
brakes in the rear. It also reduces the number of stuck 
brakes, which are in all probability indirectly caused by a 
number of light applications with the automatic brake. 

A light application of all brakes on a long train gives 
very little return in holding power for the amount of air 
used, as only a small amount of air passes into the cylinders. 
A little is lost through the leakage grooves, and much more 
in filling the space behind the pistons to the pressure required 
to overcome the resistance of the cylinder release spring and 
brake rigging. With the straight air acting only in the two 
driver and one tender brake cylinders these losses are 
insignificant. 

The absence of brake beam springs on freight cars 
requires train movement to loosen the shoes from the wheels, 
where brakes have been held on until a stop has been made. 
By rendering it safe to release the automatic at slow speeds, 
and by avoiding the use of the latter where the required 
brake power is moderate, this dragging of brake shoes can 
be avoided. 



AUTOMATIC AND STRAIGHT AIR. 145 

Fifth. — To prevent the slack from running out, and to 
aid the pressure retaining valves in controlling the speed 
while recharging on descending grades. The lower speeds 
and more thorough recharging of auxiliary reservoirs are 
thus attained, and increase the factor of train safety far 
more than is possible with the most efficient uses of 
the automatic brake on the driver and tender brakes in 
connection with the train brakes. 

Sixth. — To hold the train or locomotive and keep the 
automatic brakes recharged when standing on grades, thus 
having the train brakes ready for instant use at the start, 
which increases the factor of safety when it is necessary 
to do work on or under the engine. The application position 
of the straight air brake valve renders it impossible for the 
driver and tender brakes to leak off, and prevents the loco- 
motive from moving when no one is present, even though 
the throttle leaks. 

To many it will prove a surprising fact that, with the 
train standing and the slack bunched, straight air brakes on 
the engine and tender will hold a train on quite a heavy 
grade. In this its power is far greater than is possible with 
steam used for this purpose. The starting of undercharged 
trains, having a reduced pressure through previous brake 
application and subsequent leakage, is a dangerous feature 
too frequently met with in heavy grade service. 

Seventh. — To control speed while weighing cars; 
straight air facilitates this work and decreases rough 
handling. 

Eighth. — To increase mileage between tire turnings and 
decrease the damage to frogs and switches by badly worn 
tires. 

Ninth. — To decrease the repairs and improve the aver- 
age conditions of the automatic brake valve, by lessening the 
necessity for the use of the emergency application, as well 
as the use of the service application. 



146 AUTOMATIC AND STRAIGHT AIR. 

Tenth. — To decrease the wear ot locomotive valves and 
cylinders by eliminating the necessity for reversing when in 
motion, which is experienced with the automatic brake on 
account of its comparatively slow recharging. 

Eleventh. — To assist passenger trains in making 
smooth stops at water tanks, stations having short platforms 
and other points where accurate stops are required, and to 
hold passenger trains on grades after the automatic 
brakes are released. 

Both the automatic and straight air should always be cut 
in and ready for operation unless the failure of some part 
requires the cutting out of one or the other. 

An excess pressure of 10 pounds or over should be 
carried in the main reservoir, to insure a uniform and 
satisfactory operation. 

Positions of Straight Air and Automatic Brake 
Valves. The straight air brake valve should always be 
kept in release position when using the automatic brakes, 
and the automatic brake valve kept in running position 
when using the straight air, to prevent sticking of the 
driver and tender brakes. 

Use of Automatic Brake. Except in cases of emer- 
gency, the automatic brake must not be used on a train 
while the straight air is applied on the engine and 
tender. The straight air should be released before using 
the automatic. 

Use of Straight Air During Automatic Application. 
The use of straight air while the automatic is applied will 
not increase the driver and tender brake cylinder pressure 
above 45 pounds, yet the release of neither is assured while 
the other brake valve is in lap or application position. 

Power of Straight Air Brakes. The action of the 
straight air on the driver and tender brakes is almost as 
powerful as that of the automatic brakes. Care must be 
used when applying either brake to avoid rough handling 



AUTOMATIC AND STRAIGHT AIR. 147 

of the train, and, in holding the train down a long grade, 
to avoid loosening of tires on the drivers. When the 
straight air is used to aid in recharging trains in motion, 
the automatic should be kept inoperative by having the 
one-half-inch cocks, shown at C and D, Fig. 48, open. 

Releasing at Low Speeds. To release the train 
brakes at low speed the straight air should be applied imme- 
diately before or after moving the automatic brake valve to 
release position, and a strong straight air holding power 
maintained until all train brakes are released. Then, if no 
stop is to be made, the straight air should be gradually 
released and steam used carefully if needed until the train 
slack is all out. 

Holding or Stopping Trains With Straight Air. In 
using the straight air to slow down a train from ordinary 
speeds, to stop it on an ascending grade, or on a level at 
slow speeds, the slack should first be gradually run in or out 
according to the direction of the movement. The slower the 
speed, the more holding power the same cylinder pressure 
will give, due to the greater brake shoe friction. For this 
reason the straight air should be partially released just 
before stopping in order to relieve the coupler spring tension 
and reduce the danger of wheel sliding. If on an ascending 
grade, the straight air should be fully released as soon as the 
stop is made, and reapplied lightly as soon as the train starts 
back, in case this occurs. ' 

Piston Travel. To insure quick work and economy 
in air, the piston travel should be normal and cylinder leak- 
age avoided, both with straight air and automatic brakes. 
The piston travel increases more rapidly with straight air 
than with the automatic alone, as because of its greater use 
more frequent adjustment is necessary. 

Switching. When doing "short" switching with an 
engine having brake cylinders with long piston travel, or 
when making applications in rapid succession, to release the 



148 AUTOMATIC AND STRAIGHT AIR. 

brakes, the air pressure should be lowered only until the 
brakes do not hold. This will economize in the use of air 
and hasten the following application. The straight air brake 
valve should be kept in release position at other times when 
holding power is not wanted. 

Holding Standing Trains on Grades. To hold a 
standing train on an ascending grade, the slack should be 
taken out of the train by using the steam and then applying 
the straight air. If on a descending grade, and grade cocks 
C and D are open, the slack should be run in by using the 
straight air just as the stop is being completed; or if the 
train is already stopped, the locomotive should be reversed, 
the automatic brake valve moved to release position, and 
the straight air applied. The automatic brakes should be 
kept recharged when holding the train with the straight 
air, as this is the main object sought. 

When holding the train with straight air, the brake valve 
should be left in full application position. 

Recharging Train Brakes. When using the straight 
air to aid in recharging the train brakes when descending a 
heavy grade, grade bleed cocks C and D (Fig. 50) should 
be opened, after passing the summit of the grade. This will 
prevent the automatic from acting on the driver and tender 
brakes, but their auxiliary reservoirs will be recharged with 
those of the train. The straight air may then be used irre- 
spective of the automatic, but care must be exercised to 
avoid rough handling and overheating of the driver tires. 
If cut-out cocks C and D were not opened, and the straight 
air and automatic brakes were used alternately down heavy 
grades, driving and tender wheels would become overheated. 

The straight air should be used not only to aid in holding 
the train while recharging the brakes, but also to avoid a 
possible jerk from slack running out, when the speed is very 
low, just before releasing the brakes for the purpose of 
recharging. 



AUTOMATIC AND STRAIGHT AIR. 149 

Closing Grade Bleed Cocks. Grade bleed cocks C 
and D should always be closed on reaching the foot of a 
grade. If they are left open and a break occurs in the hose 
or brake pipe, causing a reduction of pressure in the brake 
pipe, no application of the automatic brake would follow on 
the engine and tender. 

Leaving Brakes Set. The straight air brake valve 
should remain in application position when the engine is 
brought to a stop for the purpose of oiling, taking coal and 
water, or when leaving it for a time, to insure against any 
movement of the engine. 

Engine Brakes Failing to Release. A failure of the 
driver and tender brakes to release indicates that the triple 
valves or the straight air brake valves are not in release 
position. The remedy is evident and the trouble can be 
avoided by maintaining at least 10 or 20 pounds of excess 
pressure in the mam reservoir when using the straight air, 
and keeping the straight air brake valve in release position 
when the automatic is in use. 

If the straight air brake valve is left in lap position, 
when us.'ng the automatic brake, any leak of pressure by the 
double check will bank between the double check and the 
straight air brake valve. When the automatic is released, 
reducing the pressure in the brake cylinder a trifle below that 
on the straight air side of the double check, this pressure will 
force the double check over toward the automatic side, 
closing communication between the brake cylinder and the 
triple exhaust, thus holding the brake set, and the straight air 
valve must be placed in release position in order to release 
the brake. 

If the automatic brake valve is left in full release position 
while using the straight air brake, the pressure of the main 
reservoir, brake pipe and auxiliary reservoirs will equalize, 
and in using the straight air, the main reservoir pressure will 
be reduced, which in turn will reduce the brake pipe pressure, 



150 AUTOMATIC AND STRAIGHT AIR. 

causing the triple to assume set position. This high auxiliary 
pressure feeding to the automatic side of the double check 
will force the double check over toward the straight air 
release, and in releasing the straight air brake, the only 
pressure that can be released will be that which is between 
the straight air side of the double check and the straight air 
brake valve. In order to release the brake it will then be 
necessary to wait until the brake pipe pressure exceeds that 
in the auxiliary reservoir, by placing the automatic brake 
valve in lap position, which restores the excess pressure to a 
point where it will be sufficient to overcome the pressure in 
the auxiliary. 

Drivers Sliding. If a bursted hose should cause an 
automatic application, or other conditions cause the driving 
wheels to slide, the driver brakes should be released at once 
by opening grade bleed cock D (Fig. 50). 

Wheel sliding to the extent of causing flat spots is inex- 
cusable with the straight air. As the straight air pressure is 
5 pounds lower than the automatic pressure should be when 
fully applied, it reduces the liability of wheel sliding. When 
wheel sliding, due to slippery rails, does occur, the prompt 
release of the brakes, which is possible with straight air, will 
prevent damage to the wheels. While the straight air 
pressure can be adjusted below 45 pounds, there is no neces- 
sity for so doing, as it weakens the holding power. When 
the rails are bad and the speed is low the engineman should 
not use the full straight air pressure. 

DEFECTS OF THE STRAIGHT AIR BRAKE. 

When a blow occurs from the triple exhaust while the 
straight air brake valve is being used, it indicates a leak by 
the double check from the straight air to the automatic side. 

If there is a blow at the straight air brake valve exhaust 
while using the automatic brake, it indicates that there is a 



AUTOMATIC AND STRAIGHT AIR. 151 

leak by the double check from the automatic to the straight 
air side. 

When there is a blow at the safety valve while the 
straight air is being used, it indicates that the tension of the 
spring is too weak, or that the reducing valve is not adjusted 
properly, or is held from its seat by dirt. 

If there is a blow at the straight air exhaust while the 
straight air brake is in use, it indicates that the release valve 
of the straight air is held from its seat. 

When there is a blow at the straight air exhaust when 
neither the automatic nor the straight air valve is in use, it 
indicates that application valve 8 of the straight air brake 
valve is held from its seat. 

Locating Leaks. All of the leakages previously men- 
tioned, any leakage in the pipes leading from the straight air 
brake valve to the brake cylinders, or leaks in the brake 
cylinders can be detected as follows : 

When the pressure is fully pumped up, the number of 
strokes of the pump per minute required to maintain this 
pressure should be noted. The straight air brake valve 
should then be placed in full application position and left 
until" the pressure is again restored, when the pump strokes 
should again be counted. Any difference in the number of 
strokes will indicate the leakage at one or more of the places 
mentioned. 

When the straight air brake valve is in application 
position, leakages can readily be located, as the straight air 
apparatus is constantly supplied with air from the main 
reservoir. The piston travel can also be accurately 
determined at the same time. 



152 DUPLEX MAIN RESERVOIR CONTROL. 

WESTINGHOUSE DUPLEX MAIN RES- 
ERVOIR CONTROL. 

Fig. 59 shows the general arrangement of the Westing- 
house Duplex Main Reservoir Control. This arrangement 
differs from that which is usually found on a locomotive in 
the use of the duplex pump governor, in which one head is 
adjusted for low and one for high pressure. 

The object of this arrangement is to permit the accumu- 
lation of a high main reservoir pressure, with which to 
release the brakes and recharge the auxiliary reservoirs, the 
pump being required to operate against the high pressure 
only during the time the brakes are applied. The head of the 
low pressure governor is usually adjusted at 90 pounds, 
and that of high pressure at from 120 to 130 pounds. 

. Operation. The pump governor control is transferred 
from one head to the other by the movement of the brake 
valve handle. When the brake valve is in full release or 
running position the low pressure governor controls the 
pump, and when in lap, service or emergency position the 
high pressure governor controls the pump. 

Fig. 59, being a diagrammatic view of the method of 
piping, shows the manner in which the pump governor heads 
are coupled up. The high pressure head is coupled to the 
main reservoir connection of the brake valve, while the low 
pressure head is connected with port A, which leads to the 
running position port f in the brake valve. The low 
pressure head is therefore subjected to main reservoir 
pressure when the brake valve is in running or release 
position, which allows the air pressure to pass to the low 
pressure head, causing the pump to stop when the main 
reservoir pressure is equal to the adjustment of this head. 
When the brake valve is placed in lap, service or emergency 
position, the main reservoir pressure is cut off from the feed 



DUPLEX MAIN RESERVOIR CONTROL. s « 





Fig. 59. 



154 DOUBLE PRESSURE CONTROL. 

valve and also from the low pressure governor head, and 
permits the pump to operate until the pressure in the main 
reservoir is equal to the adjustment of the high pressure 
head, which will then stop the pump. 

While the brake valve is in running or release position 
port f is closed, but air pressure reaches the low pressure 
governor head by passing back from the brake pipe through 
the feed valve attachment. 



DOUBLE PRESSURE CONTROL OR 
SCHEDULE "U." 

The double pressure control equipment is shown on 
Plate 10. It consists of simple appliances, by means of 
which the engineman can change the brake pipe and main 
reservoir pressures from one predetermined standard to 
another. 

This equipment is particularly adapted for use upon 
heavy grades, where "empties" are hauled up grades and 
"loads" down grades. A pressure of 70 pounds is carried 
in the brake pipe when the cars are empty, but this is 
increased to 90 pounds when the cars are loaded. Flat 
wheels would probably result if the higher pressure were 
carried with a train consisting of empty cars, but the higher 
braking power is so moderate in proportion to the total 
weights of cars and contents, when they are loaded, that 
danger of wheel sliding is practically eliminated. 

The difference between the schedule "U" and the high 
speed brake equipment is as follows : No additional parts 
are used on the cars with schedule "U" ; safety valves take 
the place of the reducing valves on the locomotive and 
tender equipment. 

Operation. The operation of the double pressure 
control apparatus is very similar to that of the high speed 
brake equipment. When the reversing cock handle is in 













. >•.!»• 






f v». sv.w...* 



tiitux *m cute 



c 



BKAXtCfUNOirt. 



~tArtrr vAivr 



^T^-SO* ATTACHING CAVGf 

| Torrsri/AiveoHcvuNXii 

LCAKACC. 



AUXILIARY R-[S[f)VOia. 




PLAIN T/flPLC VALV£ 




2,'cvr out cock- 



TENDER 




KAm T/>me yAive. 



CVTOUTCOCK. 

ENGINE 



PLATE 10. 



t*:v3A: 



• ■• 






DOUBLE PRESSURE CONTROL. 155 

the position opposite to that shown on Plate 10, the 
70-pound feed valve controls the brake pipe, and the entire 
apparatus will operate in the usual manner. A further 
description of the reversing cock and feed valve is given 
under the subhead "High Speed Brake." As the pump 
governor is piped in the same manner as with the ordinary 
equipment, the main reservoir pressure is cut off from act- 
ing upon the diaphragm of the pump governor when the 
brake valve is in lap, service and emergency application 
positions. While the main reservoir pressure is operative 
upon the excess pressure diaphragm when the brake valve 
is in release or running position, it is inoperative after the 
brakes have been applied and the brake valve returned to 
lap position, and the main reservoir pressure may then be 
pumped up to the limit established by the high pressure 
diaphragm. This high main reservoir pressure insures a 
prompt release and a quick recharging of the brakes upon a 
long train, and the pump operates against the high pressure 
only during the time the brakes are applied. 

When a loaded train is about to descend a long, heavy 
grade, the handle of the reversing cock is turned to its oppo- 
site position, thus cutting out the low pressure feed valve. 
The brake pipe -pressure is then controlled by the high 
pressure feed valve and the brakes are operated in the usual 
manner, but as the brake pipe and auxiliary reservoir 
pressures are now 90 pounds, a much more powerful brake 
application is available if desired. 

The purpose of the safety valves connected with the 
driver and tender brake cylinders is to prevent the accumu- 
lation of a higher cylinder pressure than 50 pounds. 

With a brake pipe pressure of 90 pounds upon freight 
trains, a reduction of about 25 pounds is necessary to cause 
the auxiliary reservoir and brake cylinder pressures to 
equalize with normal piston travel. 



156 HIGH SPEED BRAKE. 



THE HIGH SPEED BRAKE. 

The principles involved in the high speed brake are as 
follows : ( i ) The friction between the brake shoes and 
the wheel, which tends to stop the rotation of the wheel, 
becomes less as the rapidity of the rotation of the wheel 
increases. (2) The adhesion between the wheel and the 
rail remains practically constant, regardless of the speed. 

Plate 1 1 shows a modification of the quick action 
brake. The names of the parts, method of connection, and 
adjustment of the parts are indicated thereon. 

The locomotive equipment shown on Plate 1 1 can be 
changed from standard to a high speed brake by turn- 
ing the handle of the reversing cock. When this handle 
is in the position opposite to that shown on Plate 11, the 
70-pound feed valve is in service. Seventy pounds pressure 
is carried in the brake pipe when the brake valve is in 
running position, and the pump will stop when the main 
reservoir pressure reaches 90 pounds. When the brake 
valve is in lap, service or emergency position, the main 
reservoir is cut off from the excess pressure diaphragm, and 
the air pump will continue to operate until the main reservoir 
pressure reaches the limit set by the maximum governor, 
which is generally from 120 to 130 pounds, thus insuring a 
prompt release and a quick recharging of the brakes on long 
trains. 

At high speeds a greater brake cylinder pressure, with a 
corresponding increase in brake shoe pressure, can be used 
without danger of sliding wheels ; but in such cases it is also 
necessary to provide a means for reducing the high cylinder 
pressure, as the speed of the train is decreased. This is 
accomplished by means of the automatic reducing valve 
shown in the vertical cross section in Fig. 1, Plate 12. A 
horizontal cross section of this valve, through the point at 




SAfETY VALVE ?OR CXTYTA CARS WHEN TEMPORARILY 
ATTACHED TO NlffN SWED BRAKE THAWS AND 
PftOVIOO> WITH REDUCING VALVE. 



HIGH SPEED BRAKE REDUC/NG VALVE 
ADJUSTED TO RETAIN €0 IBS PRESSURE 
IN THE BRAKE CYLINDER. 



BRAKE CMNDEP. 



AttXMART RESERVOIR-. 



PASSENGER CAR 




PLATE 11. 






















~W 






HIGH SPEED BRAKE. 



157 



i'PlPETAP 

24 



T- — rr 



EX 2Q7 

EXHAUST ^- u ] 




g PIPE TAP^C^TO BRAKE CYLINDER. 



Fig. 1. 



Plate 12. 



Fig. 2. 



158 



HIGH SPEED BRAKE. 



if — 


n 


- r _ :: — — . ■ ■ 




i ■ 


3$ 




^f* 




> ^ 




\ CS "l 




} J ; ^ Uj 






S-'-i^i.':'. ^f HI 


: 






. 


i is- Haw W^ % 


• 


/-..;! 


■ : t i 9k 


I 


' ' • 




, ma 




r hbh 


; 




I ?■ 


fe' ■*.";■" . . • ~~ :: 


\wBM 




„'■.'■ ' , f 






•'. 1 ^ 






1 Ft 


| O 






Bi-ki 


I 






B Cy ■ 


11 






Si 








; -it 11 




. 




k 




• 




m 








'v*£***#l 


V 




■ 


K *^fP 








■ j^iffi^fel 


L- 




/jWBKSrtf 




pp^p^^ 


, : 


''.'!'v\Jl ■. ' .^. 


* ■ 


TA 'o' Q^. 




4 =5 . » SS 

1 3 ^* 




if £ a<^ 








■■ s5 




I *iS 




i ■ ^ 


, 


I <* 


/ 




-, ' — 


LiM 


ilb,, , — \ m 



CO 
CO 

•fH 

FN 



HIGH SPEED BRAKE. 159 

which the connecting # pipe to the brake cylinder is secured, 
is shown in Fig. 2, Plate 12. Fig. 63 shows the application 
of the valve to a car. Figs. 64, 65 and 66 are vertical cross 
sections of the upper part of the valve, showing the various 
positions of the slide valve. 

Reversing Cock. If the reversing cock handle is 
placed in the position shown, the no-pound feed valve will 
become operative, giving a brake pipe pressure of no 
pounds, and a main reservoir pressure that will correspond 
with the adjustment of the maximum pressure head of the 
pump governor. 

HIGH SPEED BRAKE REDUCING VALVE. 

Operation. When air enters the brake cylinder from 
the auxiliary reservoir, it has free access to the reducing 
valve through a pipe connected at C (Fig. 2, Plate 12), so 
that chamber d, above piston 4, is always subject to brake 
cylinder pressure. Regulating spring n, which is adjusted 
by means of nut 12, provides a resistance to the downward 
movement of piston 4, which is finally arrested by spring 
box 3. Combined with piston 4 is its stem 6, fitted with two 
collars, which control the movement of slide valve 8. Slide 
valve 8 is provided with a triangular port b in its face, which 
is always in communication with chamber d (Fig. 64). Port 
a in the slide valve seat leads directly to the atmosphere, 
through exhaust opening EX. 

Slide valve 8 and its piston 4 are shown in their normal 
positions in Fig. 64. 

It will be noted that in release position port b of slide 
valve 8 does not register with port a of its seat, so that when 
the brakes are applied the air pressure is retained in the 
brake cylinder and is subsequently released in the usual 
way, unless it becomes sufficiently high to overcome the 
tension of spring n and force piston 4 downward. 



i6o 



HIGH SPEED BRAKE. 



Service Application. When a heavy service applica- 
tion is made and the brake cylinder pressure exceeds 60 
pounds, the pressure upon piston 4 moves it downward until 







Fig. 64. 



port b in the slide valve registers with port a in its seat 
(Fig. 65), in which position any surplus brake cylinder 
pressure is promptly vented to the atmosphere. Spring 11 
then raises the piston and the slide valve to their normal 
positions, closing the exhaust port and retaining 60 pounds 
pressure in the brake cylinder. In the operation just 
described, the greatest width of port b is exposed to port a, 
and these ports are so proportioned that, in this particular 



HIGH SPEED BRAKE. 



161 



position, the surplus air is discharged from the brake 
cylinder as rapidly as it is admitted through the service 
application port of the triple valve. 

Emergency Application. The positions assumed by 
piston 4 and slide valve 8 in an emergency application of the 
brakes are shown in Fig. 66. The violent admission of air 
into the brake cylinder suddenly increases the pressure on 
piston 4, forcing it to the lower end of its stroke, in which 







Fig. 65. 



position the apex of triangular port b in the slide valve is 
brought into register with port a, and a comparatively slow 
discharge of brake cylinder pressure takes place while the 



1 62 



HIGH SPEED BRAKE. 



train is at its highest speed ; but the area of the opening of 
port b gradually increases as the decreasing pressure above 
piston 4 permits spring n to raise slowly the piston and 
slide valve. The rate of discharge thus increases as the 
speed of the train decreases. When the brake cylinder pres- 







Fig. 66. 



sure has become reduced to 6o pounds port a is closed, and 
the remainder of the brake cylinder pressure is retained 
until it is released in the usual way through the triple. 

When an emergency application of the brakes is made at 
high speeds, there is little danger of wheel sliding, and it 
will be observed that port b is so shaped that the brake 



HIGH SPEED BRAKE. 163 

cylinder pressure escapes slowly, while at lower speeds, 
where a heavy service application is more likely to occur 
and there is a greater tendency toward wheel sliding, the 
base of triangular port b is exposed, allowing the brake 
cylinder pressure to reduce quickly. 

Brake Cylinder Pressure. With an emergency appli- 
cation, the auxiliary reservoir and brake cylinder pressures 
w T ill momentarily equalize at 88 pounds, and a comparatively 
slow discharge of brake cylinder pressure will take place 
while the train is at its high speed. 

The valve is so constructed that when piston 4 moves 
to its full stroke it is arrested by shoulder 3, thus permitting 
the valve to be constantly open from the brake cylinder to 
the atmosphere while the piston and slide valve are in down- 
ward position. 

Inspection. Reducing valves should be inspected 
occasionally, to prevent possible leaks through the discharge 
port, and to ascertain that the valve closes at the proper 
pressure. 

Cars Not Equipped With Reducing Valves. Cars not 
equipped with the reducing valve should not be attached 
to trains employing the high speed brake, unless the brake 
cylinders are equipped with the safety valve provided for 
temporary use in such cases. The type "E" safety valve 
(Fig. 58) has been especially designed to prevent a pressure 
greater than standard in the brake cylinders of cars not 
equipped with the reducing valve. The safety valve may be 
quickly screwed into the oil hole of the brake cylinder head, 
and removed when the cars are again placed in ordinary 
service. 

Standard Pressures for High Speed Service. The 
standard pressures at which the different governors on the 
engine should be adjusted are as follows : The low pressure 
feed valve for the brake pipe, 70 pounds ; the high pressure 
feed valve for the brake pipe, no pounds; the excess pres- 



i6 4 HIGH SPEED BRAKE. 

sure head of the pump governor, 20 pounds differential ; the 
maximum pressure head, 140 pounds. 

Advantages of High Speed Pressure in Service 
Application. With the high speed brake it is possible 
to make two full service applications and releases without 
any prolonged effort to recharge, and still have 70 pounds 
of air in the auxiliary reservoirs with which to stop. A full 
service application here refers to a cylinder pressure of 50 
pounds, as the auxiliary reservoirs are slightly recharged 
each time the brake valve is placed in full release position to 
release the brakes. 

DEFECTS OF THE HIGH SPEED REDUCING 

VALVE. 

A failure of the brakes to remain set may be caused by 
a cut slide valve or valve seat ; a broken or improperly 
adjusted regulating spring; a worn out or defective packing 
ring 5, or packing leather 20, which would allow the air to 
pass down through the spring casing and out of the hole in 
the cap nut ; or a leak in the pipe connection leading from 
the brake cylinder to the reducing valve. 

GENERAL INFORMATION RELATING TO THE 
HIGH SPEED BRAKE. 

When using the high speed brake it should be remem- 
bered that with a brake pipe pressure of no pounds, and 
the usual piston travel, a service brake pipe reduction of 
5, 10 or 15 pounds will develop no more cylinder pressure 
than if the usual 70-pound brake pipe pressure were 
employed. If, however, when using a pressure of no 
pounds, the reduction is continued after the cylinder pres- 
sure has reached that at which the auxiliary reservoir and 
brake cylinder pressure equalize with the 70-pound brake 
pipe pressure, the cylinder pressure will increase until 
relieved by the reducing valve. 

If the brake valve is placed in service position and 



THE REVERSING COCK. 165 

allowed to remain there, the reducing valve, when it opens, 
will reduce the cylinder pressure about as fast as the triple 
valve can feed the air from the auxiliary reservoir to the 
brake cylinder. While the habit of making more than a 
20 or 25-pound service reduction is not good practice, the 
feature just described goes to show that with a service 
reduction, the cylinder pressure will not rise materially 
above that at which the reducing valve is adjusted, which 
practically eliminates any possibility of wheel sliding under 
ordinary conditions. 

The high speed brake was designed primarily to provide 
a means of stopping fast trains within a reasonable and safe 
distance, but it can also be used advantageously to save time 
in making service stops on local trains. To accomplish this 
result, when the speed of the train exceeds 30 miles per hour, 
a heavy initial reduction of from 12 to 15 pounds should be 
made, and when the speed of the train is reduced to from 
15 to 18 miles per hour a release should be made to exhaust 
the high cylinder pressure and allow the trucks to regain 
their equilibrium. A light reduction will then stop the train 
without any attendant disagreeable shock. This method of 
using the air is not only productive of quick stops, but it 
reduces the liability of wheel sliding to a minimum, as the 
low cylinder pressure is coincident with slow speed. 

THE REVERSING COCK. 

This device is a combination of a two-way cock with 
a bracket, to which are fastened the two slide valve feed 
valves required. 

Its design and appearance are shown in Fig. 67. The 
two pipe tapped openings in the back are connected by 
piping with the corresponding openings of the pipe 
bracket on the engineer's brake valve (Fig. 67). The 
opening marked "from main reservoir" connects with the 



i66 



THE REVERSING COCK. 




! .'[.' '"If- )'( Si' *iSI 














THE REVERSING COCK. 167 

feed port, which admits main reservoir pressure to the 
feed valves when the brake valve is in running position, 
and the opening marked "to brake pipe" connects with 
the brake valve port from the feed valve to the brake 
pipe. 

Operation. At all times when the brake valve is in 
running position, main reservoir pressure is admitted to 
the upper passage in the reversing cock, and thence 
through the top port in the cock plug to the openings in 
the flange on either one side or the other, which connects 
with the opening in the high pressure side of the slide 
valve feed valve. 

After passing through the feed valve, the reduced air 
pressure enters the reversing cock at the opening BP, 
and, passing through the lower passages in the reversing 
cock, is brought by the piping and port in the brake 
valve to the brake pipe. 

In this way the pressure in the brake pipe is deter- 
mined by one of the two feed valves which is brought 
into operation through the position of the reversing cock 
handle. 

The small pipe tapped opening in the top of the 
reversing cock (shown in the cut as plugged) is only for 
use with the SD-4 (old standard) type of Duplex Pump 
Governor, and, when this governor is used, it is con- 
nected with its low pressure diaphragm. It will be seen 
that the main reservoir pressure communicates with 
this opening only when the cock handle is turned 
towards the low pressure side marked "L" in front. In 
this way the low pressure governor head is cut out dur- 
ing the lap, service and emergency positions of the brake 
valve, and when the reversing cock handle is in the high 
pressure position. 

Figs. 68 and 69 illustrate the device known as the 
slide valve feed valve, which is used to reduce main 



i68 



THE REVERSING COCK. 



reservoir pressure to a predetermined brake pipe pres- 
sure, when the brake valve is in running position. One 
of these valves is attached to each side of the reversing 
cock, and its operation is fully illustrated and described 
on pages 63-67. 




Adjustment. The regulating spring 67 is generally 
adjusted to maintain a pressure of 70 pounds in the brake 
pipe by the low pressure feed valve, and 110 pounds by 
the high pressure feed valve. The details of both feed 
valves are identical. 



THE REVERSING COCK. 



169 



The defects of the slide valve feed valve are similar 
to those on the G-6 brake valve. 

If either of the pipes leading to the feed valve becomes 




broken it would be necessary to remove the pipe bracket 
from the brake valve, and connect the feed valve with the 
brake valve, which would allow the same pressure to be 
used as before. 



170 NO. 6 ET LOCOMOTIVE BRAKE. 

THE NO. 6 ET LOCOMOTIVE BRAKE 

EQUIPMENT. 

The new locomotive brake equipment here illustrated 
and described is known as the ET (engine and tender) 
brake equipment. It differs materially from the present 
combined automatic and straight air brake in that it 
consists of considerably less apparatus. In operation it 
possesses all the advantages of the latter type of brake 
equipment, and in addition several other important ones 
which are necessary in modern locomotive brake service. 

The design of the principal valves comprising the ET 
equipment is such that it may be applied to any loco- 
motive, whether in high speed passenger, double pressure 
control, ordinary passenger or freight, or any kind of 
switching service, without change or special adjustment 
of the brake apparatus. All valves are so designed that 
they may be removed for repairs and replaced without 
disturbing the pipe joints. 

In operation its important advantages are, that the 
locomotive brakes may be used with or independently 
of the train brakes, without regard to the position of the 
locomotive in the train ; the brakes can be applied with 
any desired pressure between the maximum and the 
minimum, and this pressure will be automatically main- 
tained in the locomotive brake cylinders, regardless of 
leakage from them and of variation in piston travel, 
until released by the brake valve. They can be gradu- 
ated on or off with either the automatic or the inde- 
pendent brake valve; hence, in all kinds of service the 
train can be handled without shock or danger of parting, 
and in passenger service smooth, accurate stops can be 
made with greater ease than has heretofore been possible. 



NO. 6 ET LOCOMOTIVE BRAKE. 171 

MANIPULATION. 

The instructions relating to its use are general and 
must be supplemented to a limited extent to meet fully 
the varying local conditions on different railways. 

The manipulation of the ET equipment is practi- 
cally the same as the combined automatic and straight 
air brake ; therefore, no radical departure from present 
methods of air brake practice is required to get the 
desired results. 

Positions of Brake Valve Handles. When not in 
use, the handles of both brake valves should be carried 
in running position. To make a service application, move 
the handle of the automatic brake valve to service posi- 
tion until the required brake pipe reduction has been 
made, when it should be moved to lap position, which is 
the one for holding the brakes applied. 

To release the train brakes, move the handle to 
release position and leave it there until all the triple 
valves are in release position. If the locomotive brakes 
are to be released at once the handle should be moved to 
running position, but if they are to be held for a time it 
should be moved to holding position and the brakes 
graduated off by short, successive movements between 
running and holding positions. With all freight trains, 
especially long ones, the brake valve must be left in both 
release and holding positions very much longer than 
with short trains, particularly passenger trains. 

To apply the brakes in an emergency application, 
move the handle of the automatic brake valve quickly to 
emergency position and leave it there until the train is 
stopped or the danger is past. 

To make a smooth and accurate two-application pas- 
senger train stop, the first application should be heavy 
enough to reduce the speed of the train to about 15 miles 



172 NO. 6 ET LOCOMOTIVE BRAKE. 

per hour at a convenient distance from the stopping 
point ; the train brakes should then be released by 
moving the handle to release position, and then the loco- 
motive brakes by moving the handle to running position 
for two or three seconds before making a second 
application. 

When using the independent brake only, the handle 
of the automatic brake valve should be carried in running 
position. An independent application may be released 
by moving the independent brake valve to running posi- 
tion. Release position is for use only when the automatic 
brake valve is not in running position. 

Handling Long Trains. While handling long trains 
in road or switching • service the independent brake 
should be operated with care to prevent damage to cars 
and lading, caused by running the slack in or out too 
hard. In cases of emergency arising while the inde- 
pendent brake is applied, the automatic brake should be 
applied instantly. The safety valve will restrict the 
brake cylinder pressure to the proper maximum. 

Alternating Engine and Train Brakes. The brakes 
on the locomotive and on the train should be alternated 
in heavy grade service to prevent overheating of driving 
wheel tires and to assist the pressure retaining valves 
in holding the train while the auxiliary reservoirs are 
being recharged. This is done by keeping the locomotive 
brakes released by use of the independent brake valve 
when the train brakes are applied, and applying the loco- 
motive brakes just before the train brakes are released, 
and then releasing the locomotive brakes after the train 
brakes are reapplied. 

Releasing Engine Brakes. When all brakes are 
applied automatically, to graduate off or entirely release 
the locomotive brakes only, the independent brake valve 
should be used in release position. 



NO. 6 ET LOCOMOTIVE BRAKE. 173 

Release position of the independent brake valve will 
release the locomotive brakes under any and all 
conditions. 

Engine Brake Cylinder Pressure. The red hand of 
the air gauge (Fig. ji) will show at all times the pressure 
in the locomotive brake cylinders, and this hand should 
be closely observed in brake manipulation. 

Releasing Train Brakes Before Detaching Locomo- 
tive. The train brakes should always be released before 
detaching the locomotive, and the train held with the 
hand brakes when necessary. This is especially impor- 
tant on grades, as there is otherwise no assurance that 
the car, cars or train so detached will not start when 
the air brakes leak off, as is possible where there is 
considerable leakage. 

The automatic brakes should never be used to hold 
a standing locomotive or a train, even when the loco- 
motive is not detached, for a longer time than ten min- 
utes, and not for such time if the grade is very steep or 
the condition of the brakes is not up to standard. The 
safest method is to hold the train with the hand brakes 
only and to keep the auxiliary reservoirs fully charged, in 
order to guard against a start caused by the brakes leak- 
ing off. By doing this, it is possible to obtain any part 
of the full braking power immediately after starting. 

The Independent Brake. The independent brake is a 
very important safety feature in this connection, as it 
will hold a locomotive with a leaky throttle, or quite a 
heavy train, on a fairly steep grade, if, as the automatic 
brakes are released, the slack is prevented from running 
in or out (depending on the tendency of the grade) and 
giving the locomotive a start. The best method of mak- 
ing a stop on a descending grade is to apply the inde- 
pendent brake heavily as the stop is being completed, 
thus bunching the train solidly. Then, when the train 



174 NO. 6 ET LOCOMOTIVE BRAKE. 

is stopped, the independent brake valve should be placed 
and left in application position, and the automatic brakes 
released and then recharged. If the independent brakes 
are unable to prevent the train from starting, the auto- 
matic brakes will have become sufficiently recharged to 
make an immediate stop. In such an event, enough 
hand brakes should be applied at once as are necessary 
to assist the independent brakes to hold the train. Many 
runaways and some serious wrecks have resulted through 
failure to comply with the foregoing instructions. 

When leaving the engine or while doing work about 
it, or when it is standing at a coal chute or water plug, 
the independent brake valve should always be left in 
application position. 

In case the automatic brakes are applied by a bursted 
hose, a break-in-two, or the use of the conductor's valve, 
the automatic brake valve must be placed in lap position. 

When there are two or more locomotives in a train 
the double-heading cock must be closed, and the handle 
of the automatic brake valve carried in running position 
on each engine, except the one from which the brakes are 
being operated. 

Before leaving the roundhouse the engineman should 
try the brakes with both brake valves, and should see 
that no serious leaks exist. The pipes between the dis- 
tributing valve and the brake valves must be absolutely 
tight. 

PARTS OF EQUIPMENT. 

1. The air pump, for the purpose of compressing 
the air. 

2. The main reservoirs, in which to store and cool 
the air, and collect water and dirt. 

3. A duplex pump governor, for controlling the 



NO. 6 ET LOCOMOTIVE BRAKE. 175 

pump when the pressures are attained for which it is 
regulated. 

4. A distributing valve, and small double chamber 
reservoir to which it is attached, which are placed on 
the locomotive to perform the functions of triple valves, 
auxiliary reservoirs, double check valves, high speed 
reducing valves, etc. 

5. Two brake valves, the automatic to operate the 
locomotive and train brakes, and the independent to 
operate the locomotive brakes only. 

6. A feed valve, to regulate the brake pipe pressure. 

7. A reducing vah r e, to reduce the pressure for the 
independent brake valve and for the air signal system 
when used. 

8. Two duplex air gauges, one to indicate the equal- 
izing reservoir and main reservoir pressures, the other 
to indicate the brake pipe and locomotive brake cylinder 
pressures. 

9. Driver, tender and truck brake cylinders, cut-out 
cocks, air strainers, hose couplings, fittings, etc., inci- 
dental to the piping, for purposes of brake operation. 

NAMES OF PIPING. 

Discharge Pipe: Connects the Air Pump to the first 
Main Reservoir. 

Connecting Pipe: Connects the two Main Reservoirs. 

Main Reservoir Pipe: Connects the second Main Reser- 
voir to the Automatic Brake Valve, Distributing Valve, Feed 
Valve, Reducing Valve, and Pump Governor. 

Feed Valve Pipe: Connects the Feed Valve to the Auto- 
matic Brake Valve. 

Excess Pressure Governor Pipe: Connects the Feed 
Valve Pipe to the Excess Pressure Head of the Pump 
Governor. 

Reducing Valve Pipe: Connects the Reducing Valve to 



176 XO. 6 ET LOCOMOTIVE BRAKE. 

the Independent Brake Valve, and also the Signal System 
when used. 

Brake Pipe: Connects the Automatic Brake Valve with 
the Distributing Valve and all Triple Valves on the cars in 
the train. 

Brake Cylinder Pipe: Connects the Distributing Valve 
with the Driver, Tender and Truck Brake Cylinders. 

Application Cylinder Pipe: Connects the Application 
Cylinder of the Distributing Valve to the Independent and 
Automatic Brake Valves. 

Distributing Valve Release Pipe: Connects the Applica- 
tion Cylinder Exhaust Port of the Distributing Valve to the 
Automatic Brake Valve through the Independent Brake 
Valve. 

ARRANGEMENT OF APPARATUS. 

Fig. 70 is a diagram of the No. 6 ET equipment, giving 
the necessary instructions for making the correct pipe 
connections for the equipment. Fig. 71 is a similar 
diagram giving the designations of the apparatus and 
piping as referred to in the following description : 

Referring to Fig. 71, air after being compressed by 
the pump passes to the main reservoirs and the main 
reservoir pipe. The main reservoir cut-out cock is for 
the purpose of cutting off and venting the air from the 
main reservoir pipe, when removing any of the apparatus, 
except the governor. The end toward the main reservoir 
is tapped for a connection to the pump governor. Before 
this cock is closed the double-heading cock should be 
closed, and the brake valve handle placed in release posi- 
tion. This is to prevent the slide valve of the feed valve, 
and the rotary valve of the brake valve, from being lifted 
from their seats. • 

Main Reservoir Connections. Beyond the main reser- 
voir cut-out cock the main reservoir pipe has four 



NO. 6 ET LOCOMOTIVE BRAKE. 



177 




178 NO. 6 ET LOCOMOTIVE BRAKE. 

branches, one of which runs to the automatic brake valve, 
one to the feed valve, one to the reducing valve, and one 
to the distributing valve. As a result, the automatic 
brake valve receives air from the main reservoirs in two 
ways, one direct and the other through the feed valve. 

The feed valve pipe leading from the feed valve to 
the automatic brake valve has a branch on top of the 
excess pressure head of the duplex pump governor. 

The third branch of the main reservoir pipe connects 
with the reducing valve. Air at the pressure for which 
this valve is set (45. pounds) is supplied to the inde- 
pendent brake valve through the reducing valve-pipe. 

Air Signal Connections. When the air signal system 
is installed it is connected to the reducing valve pipe, in 
which case the reducing valve also takes the place of the 
signal reducing valve formerly employed. In the branch 
pipe supplying the air signal system is placed a com- 
bined strainer, check valve and choke fitting. The 
strainer prevents any dirt from reaching the check valve 
and choke fitting. The check valve prevents air from 
flowing back from the signal pipe when the independent 
brake is applied. The choke fitting prevents the reducing 
valve from raising the signal pipe pressure so quickly as 
to prevent the operation of the signal system. 

Distributing Valve Connections. The distributing 
valve has five pipe connections made through the end of 
the double chamber reservoir, three to the left and two 
to the right. Of the three on the left, the upper is the 
supply pipe, leading from the main reservoir ; the inter- 
mediate is the application cylinder pipe, leading to the 
independent and automatic brake valves, and the lower 
is the distributing valve release pipe, leading through the 
independent brake valve to the automatic brake valve, 
when the handle of the independent brake valve is in 
running position. Of the two on the right, the lower is 



NO. 6 ET LOCOMOTIVE BRAKE. 



179 






N? Sill ^5 



I ill II \ 



>*V 



ids* 



*> % s s s> 

Pit II § 3 I i 1Mb 



180 NO. 6 ET LOCOMOTIVE BRAKE. 

the brake pipe branch connection, and the upper is the 
brake cylinder pipe, branching - to all brake cylinders on 
the engine and tender. In this pipe are placed cocks for 
cutting out the brake cylinders when necessary, and in 
the engine truck and tender brake cylinder cut-out cocks 
are placed choke fittings to prevent serious loss of main 
reservoir air, and the release of the other locomotive 
brakes during a stop, in case of a bursted brake cylinder 
hose. 

The automatic brake valve connections, other than 
those already mentioned, are the brake pipe, the main 
reservoir, the equalizing reservoir, and the lower con- 
nection to the excess pressure head of the pump 
governor. 

PRINCIPLES OF OPERATION. 

The principles governing the operation of the ET 
equipment are similar to those of other styles of equip- 
ment. The difference consists in the means for supplying 
the air pressure to the brake cylinders. Instead of a 
triple valve and auxiliary reservoir for each of the engine 
and tender equipments, the distributing valve supplies 
all brake cylinders. The distributing valve consists of 
two portions, known as the equalizing portion and the 
application portion. It is connected with a double cham- 
ber reservoir, the two chambers of which are called 
respectively the pressure and the application chambers. 
The latter is ordinarily connected with the application 
portion of the distributing valve in such a way as to 
enlarge the volume of that part of it called the applica- 
tion cylinder (Fig. 72). The connections between these 
parts, as well as their operation, may be compared with 
that of a miniature brake set, the equalizing portion 
representing the triple valve, the pressure chamber the 
auxiliary reservoir, and the application portion always 



NO. 6 ET LOCOMOTIVE BRAKE. 



i8r 



APPLICATION—^ * 

CYLINDER. f 



TO MAIN RESERVOIR. 



TO INDEPENDENT 
AUTOMATIC BRAKE 



TO INDEPENDENT BRAKE VALVE. 




APPLICATION 
CHAMBER. 



PRESSURE CHAMBER. 

ijuxtliary Reservoir 



Fig. 72. 



182 NO. 6 ,ET LOCOMOTIVE BRAKE. 

having practically the same pressure in its cylinder as 
that in the brake cylinders. This is shown by the dia- 
grammatic illustration in Fig. 72. For convenience, 
compactness and security they are combined in one 
device, as shown in Figs. 73 and 74. The equalizing 
portion and pressure chamber are used in automatic 
applications only. Reductions of brake pipe pressure 
cause the equalizing valve to connect the pressure 
chamber to the application cylinder, allowing air to flow 
from the former to the latter. The upper slide valve 
connected to the piston rod of the application portion 
admits air to the brake cylinders and is called the appli- 
cation valve, while the lower one releases the air from 
the brake cylinders and is called the exhaust valve. As 
the air admitted to the brake cylinders comes directly 
from the main reservoirs, the supply is practically unlim- 
ited. Any pressure in the application cylinder will force 
the application piston to close the exhaust valve, open 
the application valve and admit air from the main reser- 
voirs to the locomotive brake cylinders until their 
pressure equals that in the application cylinder. Also 
any variation of application cylinder pressure will be 
duplicated in the locomotive brake cylinders and the 
resulting pressure maintained, regardless of any brake 
cylinder leakage. The whole operation of this locomo- 
tive brake, therefore, consists in admitting and releasing 
air into or out of the application cylinder ; in inde- 
pendent applications, directly through the independent 
brake valve, and in automatic applications, by means of 
the equalizing portion and the air pressure stored in the 
pressure chamber. 

The well-known principle embodied in the quick 
action triple valve, by which a high braking power is 
obtained in emergency applications, and a sufficiently 
lower one in full service applications, to provide against 



NO. 6 ET LOCOMOTIVE BRAKE. 



183 



wheel sliding, is also embodied in the No. 6 distributing 
valve. This is accomplished by cutting off the applica- 
tion chamber from the application cylinder in all emer- 
gency applications. In emergency applications the pres- 
sure chamber fills the small space of the application 
cylinder only, thus giving a high equalization and a cor- 
respondingly high brake cylinder pressure. In service 
applications it must fill the same volume combined with 
that of the application chamber, thus giving a lower 
equalization and a correspondingly lower brake cylinder 
pressure. 

THE NO. 6 DISTRIBUTING VALVE. 

This valve is an important feature of the ET equip- 
ment. Fig. 73 shows the two chambers of the reservoirs. 
Safety valve 34 is also an essential part of the distributing 
valve, and is shown in Fig. 86. 

List of Parts. Referring to Figs. 73 and 74, the 
names of the different parts of this apparatus are as 
follows : 



2. 


Body. 


10. 


Application Piston. 


3. 


Application Valve 


11. 


Piston Follower. 




Cover. 


12. 


Packing Leather Ex- 


4. 


Cover Screw. 




pander. 


5- 


Application Valve. 


*3- 


Packing Leather. 


6. 


Application Valve 


14. 


Application Piston 




Spring. 




Nut. 


7- 
8. 


Application Cylinder 

Cover. 
Cylinder Cover Bolt 

and Nut. 


15- 
16. 


Application Piston 

Packing Ring. 
Exhaust Valve. 


9- 


Cylinder Cover Gas- 


17. 


Exhaust Valve Spring. 




ket. 


18. 


Application Valve Pin. 



184 



NO. 6 ET LOCOMOTIVE BRAKE. 



19. 


Application Piston 
Graduating Stem. 


35- 


20. 


Application Piston 
Graduating Spring. 


36. 


21. 


Graduating Stem Nut. 


37- 


22. 


Upper Cap Nut. 


38- 


23- 


Equalizing Cylinder 






Cap. 


39- 


24. 


Cylinder Cap Bolt and 






Nut. 


40. 


25- 


Cylinder Cap Gasket. 




26. 


Equalizing Piston. 


41. 


27. 


Equalizing Piston 






Packing Ring. 


42. 


28. 
29. 


Graduating Valve. 
Graduating Valve 


43- 




Spring. 


44. 


31- 


Equalizing Valve. 


45- 


32. 


Equalizing Valve 




Spring. 




33- 


Lower Cap Nut. 


46. 


34- 


Safety Valve. 





Double Chamber Res- 
ervoir. 
Reservoir Stud and 

Nut. 
Reservoir Drain Plug. 
Distributing Valve 

Drain Cock. 
Application Valve 

Cover Gasket. 
Application Piston 

Cotter. 
Distributing Valve 

Gasket (not shown). 
Oil Plug. 
Safety Valve Air 

Strainer. 
Equalizing Piston 

Graduating Sleeve. 
Equalizing Piston 

Graduating Spring 

Nut 
Equalizing- Piston 

Graduating Spring. 



Tracing of Ports and Connections. To simplify the 
tracing of the ports and connections, the various positions 
of this valve are illustrated in nine diagrammatic views ; 
that is, the valve is distorted to show the parts differently 
than actually constructed, with the object of explaining the 
operation clearly instead of showing the exact design of the 
parts. The chambers of the reservoir are, for convenience, 
indicated at the bottom as a portion of the valve itself. In 
Fig. 74 equalizing piston 26, graduating valve 28, and 
equalizing slide valve 31, are shown as actually constructed. 
But, as there are ports in the valves which cannot thus be 



NO. 6 ET LOCOMOTIVE BRAKE. 



i85 




Fig. 73. 



186 NO. 6 ET LOCOMOTIVE BRAKE. 

clearly indicated, the diagrammatic illustrations show each 
slide valve considerably elongated, so as to make all the ports 
appear on one plane, with similar treatment of the equaliz- 
ing valve seat. Fig. 75 shows the correct location of these 
ports. 

Main Reservoir Pressures. Referring to Fig. 76, it 
will be seen that main reservoir pressure is always present 
in the chamber surrounding application valve 5, by its con- 
nection through passage a, a, to the main reservoir pipe. 
Chamber b to the right of application piston 10 is always in 
free communication with the brake cylinders, through pas- 
sage c and the brake cylinder pipe. Application cylinder g 
at the left of application piston 10 is connected by passage h 
with the equalizing valve seat, and to the brake valves 
through the application cylinder pipe. 

AUTOMATIC OPERATION. 

Charging. Referring to Fig. 76, which shows the 
movable parts of the valve in release position, it will be seen 
that as chamber p is connected with the brake pipe, brake 
pipe air flows through feed groove y around the top of pis- 
ton 26 into the chamber above equalizing valve 31, and 
through port to the pressure chamber until the pressures 
on both sides of the piston are equal. 

Service Application. When a service application is 
made with the automatic brake valve, the brake pipe pres- 
sure in chamber p is reduced, causing a difference in pres- 
sures on two sides of this piston, which results in the piston 
moving toward the right. The first movement of the piston 
closes the feed groove and at the same time moves the grad- 
uating valve until it uncovers the upper end of port z in the 
equalizing valve 31. As the piston continues its movement 
the shoulder on the end of its stem engages the equalizing 
valve, which is then also moved to the right until the piston 
strikes equalizing piston graduating sleeve 44, graduating 



NO. 6 ET LOCOMOTIVE BRAKE. 



187 



spring 46 preventing further movement; port z in the equal- 
izing valve then registers with port h in the seat, and cavity 
11 in the equalizing valve connects ports h and w in the seat. 



^S2r— 




cm\ 



Fig. 74. 



As the equalizing valve chamber is always in communica- 
tion with the pressure chamber, air can now flow from the 
latter to both the application cylinder and the application 



t88 



NO. 6 ET LOCOMOTIVE BRAKE. 




PLAN OF 
GRADUATING VALVE. 



z .. II x 

\0 I ^ 1 



FACE OF SLIDE VALVE. 




PLAN OF SLIDE VALVE. 







O 



a-0 CH 




PLAN OF SLIDE VALVE SEAT 
Fig. 75. 



NO. 6 ET LOCOMOTIVE BRAKE. 



189 



chamber. This pressure forces application piston 10 to the 
right, as shown in Fig. jj, causing exhaust valve 16 to close 
exhaust ports e and d, and to compress application piston 



MR 




Fig. 76. 



graduating spring 20, and also causing application valve 5, 
by its connection with the piston stem through pin 18, to 
open its ports and allow air from the main reservoirs to flow 



190 



NO. 6 ET LOCOMOTIVE BRAKE. 



into chambers b, b, and through passage c to the brake 
cylinders. 

During the movement just described, cavity t in the 



MR 




Fig. 77. 

graduating valve connects ports r and s in the equalizing 
•valve, and by the same movement ports r and s are brought 
into register with ports h and / in the seat, thus establishing 



NO. 6 ET LOCOMOTIVE BRAKE. 191 

communication from the application cylinder to the safety 
valve, which is set at 68 pounds, 3 pounds above the maxi- 
mum obtained in an emergency application from a 70-pound 
brake pipe pressure, thus limiting the brake cylinder pres- 
sure to this amount. 

The amount of pressure resulting in the application 
cylinder with a certain brake pipe service reduction depends 
on the comparative volumes of the pressure chamber, appli- 
cation cylinder and its chamber. These volumes are such 
that if they are allowed to remain connected by the ports in 
the equalizing valve, with 70 pounds in the pressure cham- 
ber and nothing in the application cylinder and chamber, 
they will equalize at a pressure of about 50 pounds. 

Service Lap. When the brake pipe reduction is not 
sufficient to cause a full service application, the conditions 
described above continue until the pressure in the pressure 
chamber is reduced sufficiently below that in the brake pipe 
to cause piston 26 to force graduating valve 28 to the left 
until stopped by the shoulder on the piston stem striking 
the right-hand end of equalizing valve 31, the position 
indicated in Fig. 78, and known as service lap. In this 
position, graduating valve 28 has closed port 2 so that no 
more air can flow from the pressure chamber to the applica- 
tion cylinder and chamber, It has also closed port s, cutting 
of! communication to the safety valve, so that any leak in 
the latter cannot reduce the application cylinder pressure, 
and thus similarly affect the pressure in the brake cylinders. 

The flow of air past application valve 5 to the brake 
cylinders continues until their pressures slightly exceed that 
in the application cylinder, when the higher pressure and 
application piston graduating spring, acting together, force 
piston 10 to the left, as shown in Fig. 78, thereby closing 
port b. Further movement is prevented by the resistance of 
exhaust valve 16 and the application piston graduating 
spring, which has expanded to its normal position. The 



192 



NO. 6 ET LOCOMOTIVE BRAKE. 



brake cylinder pressure is then practically the same as that 
in the application cylinder and chamber. 

It will thus be seen that application piston 10 has appli- 



MR 




Fig. 78. 



cation cylinder pressure on one side and brake cylinder pres- 
sure on the other. When either pressure varies, the piston 
will move toward the lower pressure. Consequently if the 



NO. 6 ET LOCOMOTIVE BRAKE. 193 

pressure in chamber b is reduced by brake cylinder leakage, 
the pressure maintained in the application cylinder will force 
piston 10 to the right, opening application valve 5 and again 
admitting air from the main reservoirs to the brake cylinders 
until the pressure in chamber b' is again slightly above that 
in the application cylinder, when the piston again moves 
back to lap position. In this manner the brake cylinder 
pressure is always maintained equal to that in the applica- 
tion cylinder. This is known as the pressure maintaining 
feature. 

Automatic Release. When the automatic brake valve 
is placed in release position, and the brake pipe pressure in 
chamber p is thereby increased above that in the pressure 
chamber equalizing piston 26 moves to the left, carrying 
with it equalizing valve 31 and graduating valve 28 to the 
position shown in Fig. 76. Feed groove v now being open 
permits the pressure in the pressure chamber to increase 
until it is equal to that in the brake pipe, as before described. 

This action does not release the locomotive brakes, as 
it does not discharge the application cylinder pressure. The 
release pipe is closed by the rotary valve of the automatic 
brake valve, and the application cylinder pipe is closed by 
the rotary valve of both brake valves. To release the loco- 
motive brakes, the automatic brake valve must be moved to 
running position. The release pipe is then connected with 
the atmosphere by the rotary valve, and as exhaust cavity 
k in equalizing valve 31 connects ports i, w and h in the 
valve seat, application cylinder and chamber pressure will 
escape. As this pressure reduces, the brake cylinder pres- 
sure will force application piston 10 to the left, until exhaust 
valve 16 uncovers exhaust ports d and e, allowing the brake 
cylinder pressure to escape (Fig. 76) ; or in case of a grad- 
uated release, reduces the brake cylinder pressure in like 
proportion to the reduction in the application cylinder 
pressure. 



194 



NO. 6 ET LOCOMOTIVE BRAKE. 



Emergency. When a sudden and heavy brake pipe 
reduction is made, as in an emergency application, the air in 
the pressure chamber forces equalizing piston 26 to the right 



MR 




Fig. 79. 

with sufficient force to compress equalizing piston graduat- 
ing spring 46, so that the piston moves until it strikes the 
leather gasket beneath cap 23, as shown in Fig. 79. This 



NO. 6 ET LOCOMOTIVE BRAKE. 195 

movement causes equalizing valve 31 to uncover port h in 
the bushing, without opening port w, making a direct open- 
ing from the pressure chamber to the application cylinder 
only, so that the pressures quickly equalize. This cylinder 
volume being small and connected with that of the pressure 
chamber, a pressure of 70 pounds will equalize at about 65 
pounds. Also in this position of the automatic brake valve, 
a small port in the rotary valve allows air from the main 
reservoirs to feed into the application cylinder pipe and 
thence to the application cylinder. The application cylinder 
is now connected to the safety valve through port h in the 
seat, cavity q and port r in the equalizing valve, and port 3 
in the seat. Cavity q and port r in the equalizing valve are 
connected by a small port, the size being such that it permits 
the air in the application cylinder to escape through the 
safety valve at the same rate as the air from the main reser- 
voirs, feeding through the rotary valve of the automatic 
brake valve, can supply it, thus preventing the pressure from 
rising above the adjustment of the safety valve. 

High Speed Service. In high speed brake service the 
feed valve is regulated for no pounds brake pipe pressure 
instead of 70, and the main reservoir pressure is from 130 
to 140 pounds. Under these conditions an emergency appli- 
cation will raise the application cylinder pressure to about 
93 pounds, but the passage between cavity q and port r is 
so small that the flow of application cylinder pressure to 
the safety valve is just enough greater than the supply 
through the brake valve to decrease that pressure in prac- 
tically the same time and manner as is done by the high 
speed reducing valve, until it is approximately 75 pounds. 
The reason why the pressure in the application cylinder, 
pressure chamber and brake cylinders does not fall to 68 
pounds, to which pressure the safety valve is adjusted, is 
because the inflow of air through the brake vawe with the 
high main reservoir pressure used in high speed service is 



196 



NO. 6 ET LOCOMOTIVE BRAKE. 



equal, at 75 pounds, to the outflow through the small open- 
ing to the safety valve. This is done in order to permit of 
shorter stops in emergency applications. The application 



MR 




Fig. 80. 



portion of the distributing valve operates similarly, but more 
quickly in emergency than in service application. 

Emergency Lap. The movable parts of the valve 
remain in the position shown in Fig. 79 until the brake 



NO. 6 ET LOCOMOTIVE BRAKE. 197 

cylinder pressure slightly exceeds that in the application 
cylinder, when the application piston and application valve 
move back to the position shown in Fig. 80, which is known 
as emergency lap. 

Releasing. The release, after an emergency applica- 
tion, is produced by the same manipulation of the automatic 
brake valve as that following a service application, but the 
effect on the distributing valve is somewhat different. When 
the equalizing piston, valve and graduating valve are forced 
to release position by the increased brake pipe pressure in 
chamber p, the application chamber, with no pressure in it, is 
connected to the application cylinder, with the emergency 
pressure in it, through port w, cavity k and port h. The 
pressure in the application cylinder at once expands into 
the application chamber until these pressures are equal, 
which results in the release of brake cylinder pressure until 
it is slightly less than that in the application cylinder and 
chamber. Consequently in releasing after an emergency 
application, the brake cylinder pressure will automatically 
reduce to about 15 pounds, and it will remain at this pres- 
sure until the automatic brake valve is moved to running 
position. 

Application by Conductor's Valve, Train Parting, or 
Bursted Hose. If the brakes are applied by the use of 
a conductor's valve, a bursted hose, or the train parting, the 
movement of equalizing valve 31 breaks the connection 
between ports h and i through cavity k, so that the brakes 
will remain applied until the brake pipe pressure is restored. 
The handle of the automatic brake valve should be 'moved 
to lap position to prevent any loss of main reservoir 
pressure. 

INDEPENDENT BRAKE OPERATION. 

Independent Application. When the handle of the 
independent brake valve is moved to either application posi- 



198 



NO. 6 ET LOCOMOTIVE BRAKE. 



tion, air from the main reservoir, limited to a maximum 
pressure of 45 pounds by the reducing- valve, flows to the 
application cylinder, forcing application piston 10 to the 



MR 




Fig. 81. 



right, as shown in Fig. 81. This movement opens the port 
of application valve 5, allowing air from the main reservoirs 
to flow into chamber b, b, and through passage c to the brake 



NO. 6 ET LOCOMOTIVE BRAKE. 



199 



cylinders, as in an automatic application, until the pressure 
slightly exceeds that in the application cylinder. The appli- 
cation piston graduating spring and the higher pressure 



MR 




Fig. 82. 

then force application piston 10 to the left, until application 
valve 5 closes its port. Further movement is prevented by 
the resistance of exhaust valve 16 and the application piston 



200 NO. 6 ET LOCOMOTIVE BRAKE. 

graduating spring having expanded to its normal position. 
This position, shown in Fig. 82, is known as independent 
lap. 

It will be seen that whatever pressure exists in the appli- 
cation cylinder will be maintained in the brake cylinders by 
the pressure maintaining feature previously described. 

Independent Release. When the handle of the inde- 
pendent brake valve is moved to release position a direct 
opening is made from the application cylinder to the atmos- 
phere. As the application cylinder pressure escapes, the 
brake cylinder pressure in chambers b moves application 
piston 10 to the left, causing exhaust valve 16 to open 
exhaust ports e and d, as shown in Fig. 76, thereby allowing 
brake cylinder pressure to escape to the atmosphere. 

If the independent brake valve is returned to lap posi- 
tion before all of the application cylinder pressure has 
escaped, application piston 10 will return to independent lap 
position as soon as the brake cylinder pressure is reduced a 
little below that remianing in the application cylinder, thus 
closing exhaust ports e and d, and holding the remaining 
pressure in the brake cylinders. In this way the independent 
brake release may be graduated as desired. 

This equipment possesses all the flexibility and ease of 
manipulation embodied in the combined automatic and 
straight air equipment, with much less apparatus and com- 
plication, besides the additional important features of pres- 
sure maintaining, equal pressures in all brake cylinders, and 
the fact that it is always possible to release the locomotive 
brakes with the independent brake valve, even when auto- 
matically applied. In connection with this last-mentioned 
feature, Fig. 83 shows the positions the distributing valve 
parts will assume if the locomotive brakes are released by 
the independent brake valve after an automatic application 
has been made. This results in the application portion mov- 
ing to release position without changing the conditions in 



NO. 6 ET LOCOMOTIVE BRAKE. 



201 



either the pressure chamber or the brake pipe ; consequently 
the equalizing portion does not move until release is made 
by the automatic brake valve. 



MR 




Fig. 83. 



An independent release of locomotive brakes can also be 
made in the same manner after an emergency application 
by the automatic brake valve. However, owing to the fact 



202 NO. 6 ET LOCOMOTIVE BRAKE. 

that in this position the automatic brake valve will be sup- 
plying the application cylinder through the maintaining port 
in the rotary valve, the handle of the independent brake 
valve must be held in release position to prevent the locomo- 
tive brakes from reapplying, so long as the handle of the 
automatic brake valve remains in emergency position. The 
equalizing portion of the distributing valve will remain in 
the position shown in Figs. 79 and 80, while the application 
portion will assume the position shown in Fig. 83. 

Two or More Engines in a Train. When there are 
two or more locomotives in a train the handles of both 
brake valves on each locomotive, except the ones from which 
the brakes are being operated, should be carried in running 
position. The release pipe is then open to the atmosphere 
at the automatic brake valve, and the operation of the dis- 
tributing valve is the same as that in automatic brake appli- 
cations. In double-heading, therefore, the application and 
release of the distributing valve on each helper locomotive is 
similar to that of the triple valves on the train. But if it is 
necessary for the engineman or a helper to apply or release 
his brakes independently of those on the train he can do so 
by using the independent brake valve, without moving the 
handle of the automatic brake valve. 

Condensation. Port U drains the application cylinder 
of any moisture caused by the condensation of air in cham- 
bers b, and this moisture passes to the lower part of the dis- 
tributing valve through port m, from whence it may be 
drawn off by drain cock 38. 

Removing the Parts. To remove piston 10 and slide 
valve 16, it is necessary first to remove cover 3, application 
valve 5, and valve pin 18. 

QUICK ACTION CYLINDER CAP. 

The equalizing portion of the distributing valve, as 
already described, corresponds to the plain triple valve of 



NO. 6 ET LOCOMOTIVE BRAKE. 



203 



the old standard locomotive brake equipment. There are, 
however, conditions under which it is advisable to have it 
correspond to a quick action triple ; that is, vent brake pipe 
air into the brake cylinders in an emergency application. 
To obtain this result, cylinder cap 23 (Fig. 74) is replaced 
by the quick action cylinder cap shown in Fig. 84. 

In an emergency application, as equalizing piston 26 
moves to the right and seals against the gasket (Fig. 85), 




Fig. 84. 



the knob on the piston strikes graduating stem 59, which 
compresses equalizing piston graduating spring 46 and 
moves slide valve 48 to the right, opening port /. The brake 
pipe pressure in chamber p flows to chamber X, forces check 
valve 53 downward, and passes to the brake cylinders 
through port m in the cap and distributing valve body. 
When the pressures in the brake cylinders and the brake 
pipe equalize, check valve 53 is forced to its seat by spring 
54, thus preventing the air in the brake cylinders from flow- 
ing back into the brake pipe. When a release of the brakes 



204 



NO. 6 ET LOCOMOTIVE BRAKE. 



MR 




Fig. 85. 

occurs, and piston 26 is moved back to its normal position 
(Fig. 76), spring 46 forces graduating stem 59 and slide 
valve 48 back to the position shown in Fig. 84. 

In all other respects, the operation of a distributing valve 
provided with this cap is the same as previously described. 

DEFECTS OF THE DISTRIBUTING VALVE. 

Leaks. If application valve 5 leaks or becomes cut, 
allowing air to pass it while in lap position, it will increase 



NO. 6 ET LOCOMOTIVE BRAKE. 205 

the brake cylinder pressure above that in the application 
chamber and force application piston 10 and the application 
valve back far enough to allow the surplus air to escape at 
the brake cylinder exhaust port. This leak can be detected 
by the escape of brake cylinder air at the exhaust port dur- 
ing a brake application, or when the distributing valve is in 
release position. 

If exhaust valve 16 leaks it will cause a constant flow 
from the exhaust port while the brakes aie applied. It will 
not release the brake, as the leak will reduce the pressure 
slightly on the brake cylinder side of the piston, and the 
application pressure will move piston 10 and valve 5 so as 
to maintain a sufficient supply of air to overcome the effect 
of the leak, and the brake will not release as long as pressure 
remains in the application chamber. This leak can be 
detected by a blow from the brake cylinder exhaust port 
while the brakes are applied. 

A leaky packing leather (13) and packing ring (15) in 
the application piston would, if there were any leaks in the 
brake cylinder and the brakes were applied, allow the air 
to leak from the application chamber by the packing leather 
and ring, and both pressures would be reduced, allowing 
the brake to leak off. If on the other hand there was no 
leak by piston 10, but there was a leak in the brake cylinder, 
the air in the application chamber would hold valve 5 in 
such a position as to constantly supply the air lost through 
brake cylinder leakage. 

If equalizing slide valve 31 leaks, when both brake valves 
are in running position, there will be a slight blow at the 
emergency exhaust port of the automatic brake valve. If 
the independent brake valve is placed in application position 
there will be an increase in application chamber pressure, 
which will cause the brakes to apply with greater force than 
intended. If the automatic brake valve handle is placed in 
partial service position, the application chamber pressure will 



206 NO. 6 ET LOCOMOTIVE BRAKE. 

increase and the brakes continue to set with greater force 
until the pressures are fully equalized. If the high speed 
pressure is used, it will increase the pressure in the applica- 
tion chamber until the safety valve opens and relieves the 
application chamber of excess pressure. If the engine on 
which this leak occurred was second in a double-header, and 
air was leaking from slide valve 31 so as to allow the air in 
the application chamber to leak to the pipe leading to the 
double cut-out cock underneath the brake valve, it would 
release the brake on this engine. 

A leak in the pipe connection leading from the distribut- 
ing valve to the independent brake valve would cause the 
brake to leak off with either an automatic or an independent 
application. 

A leak in the pipe connection between the independent 
and automatic brake valves would affect an automatic appli- 
cation, but not an independent brake application. 

A leak in the pipe connection between the distributing 
valve and underneath the brake valve would have no effect 
if an application was made with the automatic brake valve, 
but if a release of an automatic application of the train 
brakes was made it would gradually destroy the holding 
features of the automatic brake valve. If an independent 
brake application was made and the handle of the inde- 
pendent brake valve was placed in lap position, this leak 
would cause a gradual release of the engine brakes. 

A leak in the pipe connection leading from the main 
reservoir to the distributing valve will have no effect on the 
brake if the air pump maintains the main reservoir pressure. 

Leaky Rotary. If the rotary valve of the independent 
brake valve leaks it will cause a slight blow at the emergency 
exhaust of the automatic brake valve, but if either the auto- 
matic or the independent brake valve is placed in partial 
service application position it will cause the pressure in the 
application chamber to increase to the maximum adjust- 



NO. 6 ET LOCOMOTIVE BRAKE. 207 

ment of the pressure reducing valve and cause the brake to 
apply with full independent pressure, while the handle of the 
automatic brake valve is in release or holding position. It 
will also cause a building up of pressure in the application 
chamber. 

Leaky Graduating Valve. If graduating valve 28 leaks 
in release position it will not affect the brakes, but if a par- 
tial service application is made it will cause the brakes to 
set harder. 

Broken Graduating Spring. If graduating spring 20 
should break, the application piston and valve would be less 
sensitive in graduating and would allow just enough more 
pressure in the brake cylinder to overcome the tension of 
graduating spring 20 and the pressure in the brake cylinder 
chamber to move piston 10 and valve 5 far enough to again 
cut off the supply of air from the brake cylinder. 

THE E-6 SAFETY VALVE. 

Fig. 86 is a sectional view of the safety valve, which is 
an essential part of the distributing valve. It is unlike the 
ordinary safety valve, as its construction is such as to cause 
it to close quickly with a "pop" action, insuring its seating 
firmly. It is sensitive in operation and responds to slight 
variations of pressure. 

List of Parts. The names of the parts composing this 
valve are as follows : 

2. Body. 5. Valve Stem. 

3. Cap Nut. 6. Adjusting Spring. 

4. Valve. 7. Adjusting Nut. 

Operation. Valve 4 is held to its seat by the com- 
pression of spring 6 between the stem and adjusting nut 
7. When the pressure below valve 4 is greater than 



208 



NO. 6 ET LOCOMOTIVE BRAKE. 




Fig. 86, 



NO. 6 ET LOCOMOTIVE BRAKE. 209 

the force exerted by the spring the valve rises, and as 
a larger area is then exposed its movement upward is 
very rapid, and is guided by the brass bushing in body 2. 
Two ports are drilled in this bushing upward to the 
spring chamber, and two outward through the body of 
the atmosphere, although only one of each of these ports 
is shown in the cut. As the valve moves upward, its lift 
is determined by stem 5 striking cap nut 3. In its move- 
ment it closes the two vertical ports in the bushing con- 
necting the valve and spring chambers, and opens the 
two lower ports leading to the atmosphere. As the air 
pressure below valve 4 decreases, and the compression 
of the spring forces the stem and vale downward, the 
valve restricts the lower ports leading to the atmosphere 
and opens those between the valve and spring chambers, 
giving the discharge air pressure access to the spring 
chamber. This chamber is always connected with the 
atmosphere by two small holes through body 2, and the 
air from the valve chamber enters more rapidly than it 
can escape through these holes, causing pressure to 
accumulate above the valve and assist the spring in 
closing it with the "pop" action previously mentioned. 

Adjustment. The safety valve is adjusted by remov- 
ing cap nut 3 and screwing up or down on adjusting nut 
7. After the proper adjustment has been made, cap 
nut 3 must be replaced and securely tightened and the 
valve operated a few times. Particular attention must be 
given to see that the holes in the valve body are always 
open and that they are not changed in size. This is of 
particular importance with reference to the two upper 
holes. 

The safety valve should be adjusted at 68 pounds. 
This adjustment is more accurately and easily made 
on a shop testing rack than in any other way. 



2IO 



NO. 6 ET LOCOMOTIVE BRAKE. 



THE H-6 AUTOMATIC BRAKE VALVE. 



This brake valve, while conforming to a considerable 
extent to the principles embodied in previous styles of 
brake valves, is necessarily different in detail, for it not 
only performs the functions of other types, but also 
performs those necessary to obtain all the desirable 
operative features of the No. 6 distributing valve. 




Plate 13, Fig. 1. 

Views. Plate 13, Figs. 1 and 2, shows two views of 
this brake valve, Fig. 1 being a plain view, with a section 
through the rotary valve chamber, the rotary valve being 
removed, and Fig. 2 a vertical section. The pipe con- 
nections are indicated in both views. 

Fig. 88 shows two views of this valve similar to those 



NO. 6 ET LOCOMOTIVE BRAKE. 



211 



on Plate 13, with the addition of a plan or top view of 
the rotary valve. The six positions of the brake valve 
handle are, beginning at the extreme left, release, run- 
ning, holding, lap, service and emergency. 



2 

3 
4 

5 
6 

7 
8 

9 
10 

11 

12 

13 




Fig. 2, Plate 13. 



List of Parts. The names 
Bottom Case. 
Rotary Valve Seat. 
Top Case. 
Pipe Bracket. 
Rotary Valve. 
Rotary Valve Key. 
Key Washer. 
Handle. 

Handle Latch Spring. 
Handle Latch. 
Handle Latch Screw. 
Handle Nut. 
Handle Lock Nut. 



of the parts are as follows: 

15. Equalizing Piston. 

16. Equalizing Piston 

Packing Ring. 

17. Valve Seat Upper 

Gasket. 

18. Valve Seat Lower 

Gasket. 

19. Pipe Bracket Gasket. 

20. Small Union Nut. 

21. Brake Valve Tee. 

22. Small Lmion Swivel. 

23. Large Union Nut. 

24. Large Union Swivel. 



212 NO. 6 ET LOCOMOTIVE BRAKE. 



. FEED VALVE 
^.PII'ETAP^I x 




MAIN RESERVOIR. 



EQUALIZING RESERYCu^ 



Fig. 88. 



NO. 6 ET LOCOMOTIVE BRAKE. 213 

25. Bracket Stud. 29. Oil Plug. 

26. Bracket Stud Nut. 30. Rotary Valve Spring. 

27. Bolt and Nut. 31. Service Exhaust Fit- 

28. Cap Screw. ting- 
Ports. Referring to the rotary valve, a, j and ^ are 

ports extending directly through it, the latter connecting 
with a groove in the face ; f and k are cavities in the valve 
face ; is the exhaust cavity ; x is a port in the face of the 
valve, connected by a cored passage with 0; Ji is a port 
extending from the face over cavity k, and connecting with 
exhaust cavity 0; n is a groove in the face, having a small 
port which connects through a cavity in the valve with 
cavity k. Referring to the ports in the rotary valve seat, 
d leads to the feed valve pipe ; b and c lead to the brake pipe ; 
g leads to chamber D ; EX is the exhaust opening leading 
out at the back of the valve ; e is the preliminary exhaust 
port leading to chamber D ; r is the warning port leading to 
the exhaust ; p is the port leading to the pump governor ; 
/ leads to the distributing valve release pipe, and u leads to 
the application cylinder pipe. 

In describing the operation of the brake valve it will 
be more readily understood if the positions are taken up 
in the order in which they are generally used, rather than 
in their regular order as given before. 

Charging and Release Position. The purpose of this 
position is to provide a large and direct passage from 
the main reservoir to the brake pipe permitting a rapid 
flow of pressure into the latter for the purpose of (11 
charging the train brake system, and (2) quickly releas- 
ing and recharging the brakes, but not releasing the 
locomotive brakes, if they are applied. 

Air at main reservoir pressure flows through port 
a in the rotary valve and port b in the valve seat to 
the brake pipe. At the same time port / in the rotary 



214 NO. 6 ET LOCOMOTIVE BRAKE. 

valve registers with equalizing port g in the valve seat, 
permitting the main reservoir pressure to enter chamber 
D above the equalizing piston. 

If the handle were allowed to remain in this position, 
the brake system would become charged to main reser- 
voir pressure. To avoid this, the handle of the brake 
valve must be moved to running or holding position. To 
prevent the engineman from forgetting this, a small port 
discharges feed valve pipe air to the atmosphere in 
release position. Cavity / in the rotary valve connects 
port d with warning port r in the seat, and allows a small 
quantity of air to escape into exhaust cavity EX, which 
makes sufficient noise to attract the engineman's atten- 
tion to the position of the brake valve handle. 

The small groove in the face of the rotary valve which 
connects with port ^ extends to port p in the valve seat, 
allowing main reservoir pressure to flow to the excess 
pressure head of the pump governor. 

Running Position. This is the proper position of 
handle ( I ) when the brake system is charged and ready for 
use; (2) when the brakes are not being operated, and (3) 
to release the locomotive brakes. In this position, cavity / 
in the rotary valve connects ports b and d in the valve seat, 
affording a large direct passage from the feed valve pipe 
to the brake pipe, so that the latter will become charged as 
rapidly as the feed valve can supply the air, but cannot 
attain pressure above that for which the feed valve is 
adjusted. Cavity k in the rotary valve connects ports c and 
g in the valve seat, so that chamber D and the equalizing 
reservoir charge uniformly with the brake pipe, keeping the 
pressure on the two sides of the equalizing piston equal. 
Port 6" in the rotary valve registers with port p in the valve 
seat, permitting main reservoir pressure, which is present 
at all times above the rotary valve, to pass to the excess 
pressure head of the pump governor. Port /? in the rotary 



NO. 6 ET LOCOMOTIVE BRAKE. 215 

valve registers with port / in the seat, connecting the dis- 
tributing valve release pipe through exhaust cavity EX 
with the atmosphere. 

If the brake valve is in running position when uncharged 
cars are cut in, or if, after a heavy brake application and 
release, the automatic brake valve is returned to running 
position too soon, the governor will stop the pump until the 
difference between the hands on gauge No. 1 is less than 
20 pounds. The stoppage of the pump directs the engine- 
man's attention to his improper operation of the brake valve, 
as running position results in delay in charging, and is 
liable to cause some brakes to stick. Release position should 
be used until all brakes are released and the brake system 
is nearly charged. 

Service Position. This position gives a gradual 
reduction of brake pipe pressure, causing a service applica- 
tion. Port h in the rotary valve registers with port e in the 
valve seat, allowing air from chamber D and the equalizing 
reservoir to escape to the atmosphere through cavities in 
the rotary valve and EX in the valve seat. Port c i 
restricted so that pressure in chamber D and the equalizing 
reservoir will be reduced gradually. 

As all other ports are closed, the reduction of chamber 
D pressure allows the brake pipe pressure under the equaliz- 
ing piston to raise it and unseat its valve, allowing brake 
pipe air to flow to the atmosphere gradually, through the 
opening marked BP Ex. When the pressure in chamber D 
is reduced to the desired amount, the brake valve handle is 
moved to lap position, thus stopping any further reduction 
in chamber D pressure. Air will then continue to flow from 
the brake pipe until its pressure has fallen to a trifle less 
than that retained in chamber D, permitting the pressure in 
this chamber to force the piston downward gradually and 
stop the discharge of brake pipe air. It will thus be seen 
that the amount of reduction in the equalizing reservoir 



216 NO. 6 ET LOCOMOTIVE BRAKE. 

determines the reduction in brake pipe pressure, regardless 
of the length of the train. 

The gradual reduction in brake pipe pressure is to pre- 
vent quick action of the brakes, and the gradual stoppage 
of the brake pipe discharge is to prevent the premature 
release of the head brakes. 

Lap Position. This position is used while holding the 
brakes applied after a service application until it is desired 
either to make a further brake pipe reduction or to release 
the brakes, and to prevent loss of main reservoir pressure 
in the event of a bursted hose, a break-in-two, or the open- 
ing of the conductor's valve. In this position, all ports are 
closed. 

Release Position. This position, which is used for 
releasing the train brakes after an application, without 
releasing the locomotive brakes, has already been described 
under Charging and Release. The air flowing from the 
main reservoir pipe connection through port a in the rotary 
valve and port b in the valve seat to the brake pipe, raises 
the pressure in the latter, thereby causing the triple valves 
and the equalizing portion of the distributing valve to go to 
release position, which releases the train brakes, and 
recharges the auxiliary reservoirs and the pressure chamber 
in the distributing valve. When the brake pipe pressure 
has been increased sufficiently to cause this, the handle of 
the brake valve should be moved either to running or hold- 
ing position ; the former when it is desired to release the 
locomotive brakes and the latter when they are still to be 
held applied. 

Holding Position. This position is so named because 
the locomotive brakes are held applied while the train 
brakes recharge to feed valve pressure. All ports register 
as in running position except port /_, which is closed. 

Therefore the only difference between running and 



NO. 6 ET LOCOMOTIVE BRAKE. 217 

holding positions is that in the former the locomotive brakes 
are released, while in the latter they are held applied. 

Emergency Position. This position is used when the 
most prompt and heavy application of the brakes is required. 
Port x in the rotary valve registers with port c in the valve 
seat, making a large and direct communication between the 
brake pipe and atmosphere through cavity in the rotary 
valve and EX in the valve seat. This direct passage makes 
a sudden and heavy discharge of brake pipe pressure, caus- 
ing the triple valves and distributing valve to go to emer- 
gency position and give the maximum braking power in 
the shortest possible time. 

In this position, main reservoir air flows to the applica- 
tion cylinder through port j, which registers with a groove 
in the seat connecting with cavity k ; thence through ports n 
in the valve and u in the seat to the application cylinder 
pipe, thereby maintaining application cylinder pressure. 

Lubrication. Oil plug 29 is placed in top case 4, at 
a point to fix the level of an oil bath in which the rotary 
valve operates. The position of this oil hole is such that it 
is impossible to pour oil into the valves in excess of the 
amount required. This arrangement furnishes thorough 
lubrication. Valve oil should be used. 

Preventing Leakage. Leather washer 8 prevents air 
in the rotary valve chamber from leaking past the rotary 
valve key to the atmosphere. Spring 30 keeps the rotary 
valve key firmly pressed against washer 8 when no main 
reservoir pressure is present. Handle 9 contains latch 11, 
which fits into notches in the quadrant of the top case, so 
located as to indicate the different positions of the brake 
valve handle. Handle latch spring 10 forces the latch 
against the quadrant with sufficient pressure to indicate 
each position. 

Removing the Parts. To remove the brake valves, 



218 NO. 6 ET LOCOMOTIVE BRAKE. 

the cocks should be closed and nuts 27 taken off. To take 
the valve proper apart, cap screws 28 should be removed.' 

The brake valve should be located so that the engineer 
can operate it conveniently from his usual position, while 
looking forward or back out of the side cab window. 

THE S-6 INDEPENDENT BRAKE VALVE. 

Fig. 89 shows a vertical section through the center of 
the valve and a horizontal section through the valve body, 
with the rotary valve removed, showing the rotary valve 
seat. Fig. 90 shows this valve similarly to Fig. 89, with the 
addition of a top view of the rotary valve. In these views 
the pipe connections and positions of the handle are indi- 
cated. 

List of Parts. Referring to Fig. 90, the names of the 
parts are as follows : 



2. 


Pipe Bracket. 


16. 


Latch Spring. 


3- 


Rotary Valve Seat. 


17- 


Latch Screw. 


4- 


Valve Body. 


18. 


Latch. 


5- 


Return Spring Casing. 


19. 


Cover Screw. 


6. 


Return Spring. 


20. 


Oil Plug. 


7- 


Cover. 


21. 


Bolt and Nut. 


8. 


Casing Screw. 


22. 


Bracket Stud. 


9- 


Rotary Valve. 


23- 


Bracket Stud Nut. 


10. 


Rotary Valve Key. 


24. 


Upper Gasket. 


11. 


Rotary Valve Spring. 


25- 


Lower Gasket. 


12. 


Key Washer. 


26. 


Lower Clutch. 


13- 


Upper Clutch. 


27. 


Return Spring Stop 


14. 


Handle Nut. 


28. 


Cap Screw. 


15. 


Handle. 







Ports and Grooves. Port b in the seat leads to the 
reducing valve pipe. Port a leads to that portion of the 
distributing valve release pipe which connects to the dis- 



NO. 6 ET LOCOMOTIVE BRAKE. 



219 




Fig. 89. 



tribtiting valve at IV (Fig. 76). Port c leads to the other 
portion of the release pipe which connects to the automatic 
brake valve at III (Fig. 87). Port d leads to the applica- 
tion cylinder pipe which connects to the distributing valve 



220 



NO. 6 ET LOCOMOTIVE BRAKE. 



23 UH'p\PZ TAP 







~z 



) 



NO. 6 ET LOCOMOTIVE BRAKE. 221 

at II (Fig. 76). Port h in the center is the exhaust port 
leading directly down to the atmosphere. Port k is the 
warning port, connecting with the atmosphere. Exhaust 
cavity g in the rotary valve is always in communication at 
one end with the exhaust port h. Groove e in the face of 
the valve communicates at one end with a port through the 
valve. This groove is always in communication with a 
groove in the seat connecting with supply port b, and 
through the opening just mentioned air is admitted to the 
chamber above the rotary valve, thus keeping it to its seat. 
Port m connects by a small hole with groove e ; f is a groove 
in the face of the rotary valve ; / consists of ports in top 
and face of valve connected by a passage. 

Running Position. This is a position in which the 
independent brake valve should be carried at all times when 
the independent brake is not in use. Groove f in the rotary 
valve connects ports a and c in the valve seat, thus estab- 
lishing communication between the application cylinder of 
the distributing valve and port / of the automatic brake 
valve (Fig. 87), so that the distributing valve can be 
released by the latter. It will also be noted that if the auto- 
matic brake valve is in running position, and the inde- 
pendent brakes are being operated, they can be released by 
simply returning the independent valve to running position, 
as the application cylinder pressure can then escape through 
the release pipe and automatic brake valve. 

Slow Application Position. To apply the independ- 
ent brakes lightly or gradually, the brake valve handle 
should be moved to slow application position. Port m then 
registers with port d, allowing air to flow from the reducing 
valve pipe through port and groove b in the seat, groove e 
in the rotary valve, and the comparatively small port m to 
port d; thence through the application cylinder pipe to the 
application cylinder of. the distributing valve. 

Quick Application Position. To obtain a quick appli- 



222 



NO. 6 ET LOCOMOTIVE BRAKE. 



>8 
I 



i 
8 




Fig. 91. 



NO. 6 ET LOCOMOTIVE BRAKE. 223 

cation of the independent brake, the brake valve should be 
moved to quick application position. Groove e then con- 
nects ports b and d directly, making a larger opening 
between them than in the slow application position, and 
allowing supply air to flow rapidly from the reducing valve 
pipe to the application cylinder of the distributing valve. 
Since the supply pressure to this valve is determined by the 
adjustment of the reducing valve at 45 pounds, this is the 
maximum cylinder pressure that can be obtained. 

Lap Position." This position is used to hold the inde- 
pendent brake applied after the desired cylinder pressure is 
obtained, at which time all communication between the oper- 
ative ports is closed. 

Release Position. This position is used to release the 
pressure from the application cylinder when the automatic 
brake valve is not in running position. At such time, the 
offset in cavity g registers with port d, allowing pressure 
in the application cylinder to flow through the application 
cylinder pipe, ports d, g and h to the atmosphere. 

Purpose of Return Spring 6. The purpose of return 
spring 6 is to move handle 15 automatically from release to 
running position, or from quick application to slow applica- 
tion position, as soon as the engineman lets go of it. The 
automatic return from release to running position is to 
prevent the engineman from leaving the handle in the for- 
mer position, and thereby make it impossible to operate the 
locomotive brake with the automatic brake valve. The 
action of the spring between quick application and slow 
application positions serves to accentuate the latter, so that 
in rapid operation of the valve the engineman is less likely 
unintentionally to pass over it to quick application positon, 
thereby obtaining a heavy application of the locomotive 
brake when only a light one was desired. As a warning to 
the engineman in case of a broken return spring, port / in 
the face of the rotary registers in release position with port 



224 NO. 6 ET LOCOMOTIVE BRAKE. 

k in the seat, allowing air to escape to the atmosphere. 

Oil Plug. The purpose of oil plug 20 is the same as 
that previously described in the automatic brake valve 
section. 

Fig. 91 gives a top view of both brake valves, showing 
the position of their handles. 

THE B-6 FEED VALVE. 

The B-6 feed valve, furnished with the No. 6 equipment, 
is an improved form of the slide valve type. It differs from 
previous types in charging to the regulated pressure some- 
what quicker, and in maintaining the pressure more accu- 
rately under the variable conditions of short and long trains, 
and of good and poor maintenance. It also gives high and 
low brake pipe pressure control. It is supplied with air 
directly from the main reservoir. It regulates the pressure 
in the feed pipe valve, and also the brake pipe in running 
and holding positions of the automatic brake valve, as the 
latter then connects the two pipes. It is connected to a pipe 
bracket located in the piping between the main reservoir 
and the automatic brake valve, and is interchangeable with 
previous types. 

Figs. 92 and 93 are diagrammatic views of the valve 
and pipe bracket, showing the ports and operative parts on 
one plane to facilitate description. 

List of Parts. The names of the parts are as follows : 



2. 


Valve Body. 


10. 


Supply Valve Spring. 


3- 


Pipe Bracket. 


11. 


Regulating Valve Cap. 


5- 


Cap Nut. 


12. 


Regulating Valve. 


6. 


Piston Spring. 


13- 


Regulating Valve Spring 


7- 


Piston Spring Tip. 


14. 


Diaphragm. 


8. 


Supply Valve Piston. 


15- 


Diaphragm Ring. 


9- 


Supply Valve. 


16. 


Diaphragm Spindle. 



NO. 6 ET LOCOMOTIVE BRAKE. 



225 



17. Regulating Spring. 20. Lower Stop. 

18. Spring Box. 21. Stop Screw. 

19. Upper Stop. 22. Adjusting Handle. 

This feed valve consists of two sets of parts, the supply 
and regulating. The supply parts, which control the flow 




Fig. 92. 



226 



NO. 6 ET LOCOMOTIVE BRAKE. 




Fig. 93. 



of air through the valve, consist of supply valve 9 and its 
spring 10; supply valve piston 8 and its spring 6. 

Regulating Parts. The regulating parts consist of 
the Regulating Valve 12, Regulating Valve Spring 13, Dia- 



NO. 6 ET LOCOMOTIVE BRAKE. 227 

phragm 14, Diaphragm Spindle 16, Regulating Spring 17, 
and Adjusting Handle 22. 

Main Reservoir Pressure. Alain reservoir air enters 
through port a, a, to the supply valve chamber B, forces 
supply valve piston 8 to the left, compresses piston spring 
6, and causes the port in supply valve 9 to register with port 
c (Fig. 93). This permits air to pass through ports c and d 
to the feed valve pipe at FVP, and through port e to dia- 
phragm chamber L. 

Regulating valve 12 is then open and connects chamber 
G, on the left of piston 8, to the feed valve pipe through 
passage h, port k, chamber L, and passage e, d, d. Air feed- 
ing by the piston cannot accumulate above feed valve pipe 
pressure. When regulating valve 12 is closed the pressure 
on the left of piston 8 quickly rises to the main reservoir 
pressure on the right, and piston spring 6 forces piston 8 
and supply valve 9 to the right, closing port c and stopping 
the flow of air to the feed valve pipe. 

Regulating Valve. The regulating valve is operated 
by diaphragm 14. When the pressure of regulating spring 
17 on its right is greater than the feed valve pipe pressure 
in chamber L on its left, it opens regulating valve 12. This 
causes the supply valve to admit air to the feed valve pipe. 
When the feed valve pipe pressure in chamber L becomes 
greater than the tension of regulating spring 17, the dia- 
phragm allows regulating valve 12 to close. This causes 
the supply valve to stop admitting air to the feed valve pipe. 

As previously explained, in release position of the H-6 
automatic brake valve, the warning port is supplied from the 
feed valve pipe. This insures that the excess pressure gov- 
ernor head will regulate the brake pipe pressure in release 
position even though the feed valve is leaking slightly, but 
not enough to be otherwise detrimental. 

Distinguishing Feature. The distinguishing feature 
of this type of feed valve is the duplex adjusting arrange- 



228 NO. 6 ET LOCOMOTIVE BRAKE. 

ment by which it eliminates the necessity of the two feed 
valves in high and low pressure service. The spring box 
18 has two rings encircling it, which are split through the 
lugs marked 19 and 20 in the diagram, and which may be 
secured in any position by screw 21. The pin forming part 
of adjusting handle 22 limits the movement of the handle 
to the distance between stops 19 and 20. When testing the 
valve, stop 19 is located so that the compression of spring 
17 will give the desired high brake pipe pressure, and stop 
20 is located so that the spring compression is enough less 
to give the low brake pipe pressure. Thereafter, by simply 
turning handle 22 until its spring strikes either one of these 
stops, the regulation of the feed valve is changed from one 
brake pipe pressure to the other. 

Adjustment, To adjust this valve, screws 21 should 
be slackened, which allows stops 19 and 20 to turn around 
spring box 18. Adjusting handle 22 should be turned until 
the valve closes at the lower brake pipe pressure desired, 
when stop 20 should be brought in contact with the handle 
pin, at which point it should be securely fastened by tight- 
ening screw 21. Adjusting handle 22 should then be turned 
until the higher adjustment is obtained; when stop 19 is 
brought in contact with the handle pin and securely fast- 
ened. The stops should be placed to give no pounds high 
and 70 pounds low brake pipe pressure. 

When replacing this feed valve on its pipe bracket after 
removal, the gasket must always be in place between the 
valve and bracket to insure a tight joint. 

THE C-6 REDUCING VALVE. 

This valve is the well-known feed valve that has been 
used for many years in connection with the G-6 brake valve, 
but in this equipment it is attached to a pipe bracket. The 
only difference between it and the B-6 feed valve just 



NO. 6 ET LOCOMOTIVE BRAKE. 229 

described is in the adjustment, it being designed to reduce 
main reservoir pressure to a single fixed pressure, which 
in this equipment is, as already stated, 45 pounds. To adjust 
this valve, the cap nut on the end of the spring box should 
be removed ; this will expose the adjusting nut, by which 
the adjustment is made. It is called a reducing valve when 
used with the independent brake and air signal systems, 
simply to distinguish it from the feed valve supplying the 
automatic brake valve. 

THE SF PUMP GOVERNOR. 

The duty of the SF pump governor is to restrict the 
speed of the pump sufficiently when the desired main reser- 
voir pressure is obtained, preventing this pressure from ris- 
ing any higher. During most of the time when on the road 
the automatic brake valve is in running position, keeping 
the brakes charged. But little excess pressure is then 
needed and the governor regulates the main reservoir pres- 
sure to only about 20 pounds above the brake pipe pressure, 
thus making the work of the pump easier. On the other 
hand, when the brakes are applied, a high main reservoir 
pressure is needed to insure their prompt release and 
recharge. Therefore, as soon as the use of lap, service, or 
emergency position is commenced, the governor allows the 
pump to work freely until the maximum main reservoir 
pressure is obtained. Again, when the brake pipe pressure 
is changed from one amount to another by the feed valve, 
as where a locomotive is used alternately in high speed 
brake and ordinary service, the governor automatically 
changes the main reservoir pressure to the maximum, and 
at the same time maintains the other features just^described. 

Another important feature is that, before commencing 
and during the descent of steep grades, this governor 
enables the engineman to raise and maintain the brake pipe 



230 NO. 6ET LOCOMOTIVE BRAKE. 

pressure about 20 pounds above the feed valve regulation 
merely by the use of release position of the automatic brake 
valve, the position which should be used during such 
braking. 

Construction and Operation. Fig. 94 shows a sec- 
tional view of this governor with steam valve 5 open. Con- 
nection B leads to the boiler; P to the air pump; MR to the 
main reservoir ; ABV to the automatic brake valve ; FVP 
to the feed valve pipe, and W is the waste pipe connection. 
Steam enters at B and passes by steam valve 5 to connection 
P, and thence to the pump. The governor regulating head 
on the left is called the excess pressure head and the one on 
the right the maximum pressure head. Air from the main 
reservoirs flows through the automatic brake valve (when 
the latter is in release, running or holding position) to the 
connection marked ABV into chamber d below diaphragm 
28. Air from the feed valve pipe enters at the connection 
FVP to chamber / above diaphragm 28, adding to the pres- 
sure of regulating spring 2J in holding it down. As this 
spring is adjusted to about 20 pounds, this diaphragm will 
be held down until the main reservoir pressure in chamber 
d slightly exceeds the combined air and spring pressure in 
chamber /. At such time, diaphragm 28 will rise, unseat 
its pin valve and allow air to flow to chamber b above the 
governor piston, forcing the latter downward, compressing 
its spring, and restricting the flow of steam past steam valve 
5 to the point where the pump will just supply the leakage 
in the brake system. When main reservoir pressure in 
chamber d becomes reduced, the combined spring and air 
pressure above the diaphragm forces it down, seating its pin 
valve. 

As chamber b is always open to the atmosphere through 
the small vent port c, the pressure in chamber b above the 
governor piston will then escape to the atmosphere and 
allow the piston spring and steam pressure below valve 5 



NO. 6 ET LOCOMOTIVE BRAKE. 



231 




-an 



Fig. 94. 



to raise it and the governor piston to the position shown. 
Since the connection from the main reservoir to chamber d 
is open only when the handle of the automatic brake valve 
is in release, running or holding position, in the other posi- 
tions this governor head is cut out. The connection marked 
MR in the maximum pressure head should be connected to 



232 NO. 6 ET LOCOMOTIVE BRAKE. 

the main reservoir cut-out cock, or to the pipe connecting 
the two main reservoirs, in order to be always in communi- 
cation with the main reservoir, so that when the excess 
pressure head is cut out by the brake valve, or by the main 
reservoir cut-out cock, this head will control the pump. 
When main reservoir pressure in chamber a exceeds the 
tension of spring 19 in the maximum pressure head, dia- 
phragm 20 will raise its pin valve and allow air to flow into 
chamber b above the governor piston, controlling the pump 
as above described. The adjustment of spring 19 thus 
forms the maximum limit of main reservoir pressure, as, for 
example, when the train brakes are applied. 

As each governor head has a vent port c, from which a 
small amount of air escapes whenever pressure is present in 
port b, to avoid an unnecessary waste of air, one of these 
should be plugged. 

Adjustment. To adjust the excess pressure head of 
this governor, cap nut 25 should be removed and adjust- 
ing nut 26 turned until the compression of spring 27 
gives the desired difference between main reservoir and 
brake pipe pressures, the handle of the automatic brake 
valve being in running position. To adjust the maximum 
pressure head, cap nut 17 should be removed and adjust- 
ing nut 18 turned until the compression of spring 19 
causes the pump to stop at the maximum main reservoir 
pressure required, the automatic brake valve now being 
in lap position. Spring 2J should be adjusted for 20 
pounds excess pressure, and spring 19 for a pressure 
ranging from 120 to 140 pounds, depending on the service 
required. 



NO. 6 ET LOCOMOTIVE BRAKE. 



233 



THE "DEAD ENGINE" FEATURE. 

The "dead engine" feature shown in Fig. 71 is for the 
operation of locomotive brakes when the pump on a 
locomotive in a train is inoperative, through being broken 
down by reason of lack of steam. Fig. 95 shows the 
combined strainer, check valve and choke fitting. As 
these parts are not required at other times, a cut-out 




Fig. 95. 

cock is provided. This cock should be kept closed except 
under the conditions just mentioned. The air for oper- 
ating the brakes on such a locomotive must then be 
supplied through the brake pipe from the locomotive 
operating the train brakes. 

Operation. With the cut-out cock open, air from the 
brake pipe enters at BP (Fig. 95), passes through the 
curled hair strainer 5, lifts check valve 4, which is held 
to its seat by spring 2, passes through the choke bushing, 
and out at MR to the main reservoir, thus providing 
pressure* for operating the brakes on this locomotive. 
The double-heading cock should be closed, and the handle 
of each brake valve should be in running position. Where 
absence of water in the boiler, or some other reason, 
justifies keeping the maximum braking power of such 



234 NO. 6 ET LOCOMOTIVE BRAKE. 

a locomotive lower than the standard, this can be accom- 
plished by reducing the adjustment of the safety valve 
on the distributing valve. It can also be reduced at will 
by the independent brake valve. 

The strainer protects the check vaive and choke from 
dirt. Spring 2 over the check valve insures this valve 
seating and, while assuring an ample pressure to operate 
the locomotive brakes, keeps the main reservoir pressure 
somewhat lower than the brake pipe pressure, thereby 
reducing any leakage from the former. The choke pre- 
vents a sudden drop in brake pipe pressure and the 
application of the train brakes, that would otherwise 
occur with an uncharged main reservoir cut into a 
charged brake pipe. In this it operates similarly to the 
feed groove in a triple valve. 

PUMP FAILURE WHEN DOUBLE-HEADING 
WITH ET EQUIPMENT. 

When double-heading, and the air pump is out of 
order on the second engine, the brakes on this engine 
could not be operated from the leading engine, as the 
pressure used for applying these brakes comes from the 
main reservoir of the second engine. The distributing 
valve on the second engine would operate, as the pressure 
chamber would be charged from the leading engine ; 
consequently these valves would respond to reductions 
in brake pipe pressure made by the leading engine. The 
brakes on the second engine would not apply, however, 
on account of lack of air in the main reservoir, which 
should pass to the brake cylinder when the distributing 
valves are operated. 

The engineman of the second engine can, however, 
in cases of pump failure, gain control of his engine brakes 
by placing the automatic brake valve handle in full 
release position and slowly turning the cut-out cock 



NO. 6 ET LOCOMOTIVE BRAKE. 235 

underneath the brake valve, allowing the main reservoir 
to charge from the brake pipe, providing the engine is 
not equipped with the "dead engine" feature. When the 
main reservoir is charged to brake pipe pressure, the 
cut-out cock should be returned to its former position in 
order to allow the proper operation of the train brakes. 

An additional provision is made for charging the main 
reservoir of the second engine from the leading engine. 
A few extra parts are furnished, by means of which the 
main reservoir can be charged through a by-pass, con- 
taining a non-return check valve, strainer, cut-out cock 
and a diaphragm, which necessitates a flow of air from 
the brake pipe in such a manner that the air taken from 
it will not apply the train brakes while the main reservoir 
is being charged. 

TERMINAL TESTS, AND HOW TO LOCATE 

AND REMEDY DEFECTS OF THE 

WESTINGHOUSE NO. 6 ET 

EQUIPMENT. 

As reported to the traveling engineers' convention by the com- 
mittee on terminal tests, and the locating of defects, at Detroit, 
August 25, 1908. 

AIR GAUGE TEST. 

In all air brake testing it is deemed of first importance 
that the air gauges be tested and be known to be correct. 
To test the air gauges, the inspector should be provided 
with a test gauge that is known to be correct, and he 
should then proceed in the following manner : 

Start the air pump and charge the system to full 
pressure, then place the automatic brake valve handle 
in release position. With test gauge coupled to the 
front pipe hose, note main reservoir, equalizing reservoir 



236 NO. 6 ET LOCOMOTIVE BRAKE. 

and brake pipe pressures. The air gauges should indicate 
the same pressures as the test gauge. To test brake 
cylinder gauge, connect test gauge to the brake cylinder, 
and then make a brake application. If the brake cylinder 
hand on the brake cylinder gauge registers with the test 
gauge it is correct ; if any of the locomotive air gauges 
do not register with test gauge, they are out of adjust- 
ment the amount of difference. 

Another method of testing the brake cylinder gauge 
is to make a service application, noting carefully the 
exact amount of brake pipe reduction. The brake cylin- 
der gauge, if correct, will register, within a pouitd or 
two, two and one-half pounds of cylinder pressure for 
each pound of brake pipe reduction. For example, if 
the brake pipe reduction is exactly ten pounds, the brake 
cylinder pressure registered should be twenty-five 
pounds. 

BRAKE PIPE LEAKAGE TEST. 

To test the brake pipe for leakage, make a five-pound 
service reduction from a seventy-pound brake pressure 
and note the fall in brake pipe pressure as indicated by 
the brake pipe air gauge, not by the equalizing reservoir 
gauge. This leakage should not exceed five pounds per 
minute. 

FEED VALVE TEST. 

After releasing brakes and recharging- the system to 
maximum pressure, open the angle cock at rear of tender 
sufficiently wide to produce a leak equivalent to a brake 
pipe leakage of from seven to ten pounds per minute, and 
observe the brake pipe gauge pointer. The fluctuation 
of this pointer will indicate the opening and closing 
points of the feed valve, which should not vary more 
than two pounds. If the gauge hand does not fluctuate 



NO. 6 ET LOCOMOTIVE BRAKE. 237 

at all, it is an indication that the supply valve piston is 
too loose, and that the brake pipe leakage is being sup- 
plied past both this piston and the regulating valve. If 
the fluctuation is more than two pounds it indicates a 
dirty or a sticky condition of the operating parts of the 
valve. 

GOVERNOR TEST. 

Unless the standard excess pressure of the road is 
different when the automatic brake valve handle is in 
running position, the main reservoir pressure should be 
twenty pounds more than the brake pipe pressure ; and 
when the automatic brake valve handle is on lap position, 
the main reservoir pressure should increase to the adjust- 
ment of the high pressure governor top. Here it should 
be observed whether the high pressure top is adjusted to 
maintain a higher pressure than the low pressure top or 
not; if it does not, it should be made to do so. 

If the main reservoir pressure is more or less than 
the standard for the road, with the automatic brake valve 
handle in running position, it indicates that the regulating 
spring in the excess or low pressure governor top is out 
of adjustment. This spring should then be adjusted, 
which can be done by removing the check nut and screw- 
ing the regulating nut down or up, as the case may 
require. In this test it is important that the brake pipe 
pressure be known to be correct, because it is this 
pressure, in addition to the spring pressure, that operates, 
the excess pressure governor. 

With the automatic brake valve handle on lap posi- 
tion, the low pressure governor top is cut out, so that 
any variation from the standard of the road, with the 
handle in this position, will be caused by the high pressure 
governor top. 



238 NO. 6 ET LOCOMOTIVE BRAKE. 

AUTOMATIC BRAKE VALVE TEST. 

The handle of the automatic brake valve should 
operate easily ; if it does not, it is probably due to a dry 
rotary valve or to a dry rotary valve key gasket. This 
trouble may be remedied by closing first the brake valve 
cut-out cock, then the main reservoir cut-out cock, and 
after the pressure has blown off, removing the oil plug 
in the valve body and filling the oil hole with good oil, 
then moving the handle a few times from full release to 
emergency position and back to give the oil a chance 
to work in between the rotary and its seat. After this 
operation again fill the oil hole and replace the oil plug. 
Next remove the cap nut from the rotary valve key, fill 
the oil hole and push down on the key, then fill up the 
hole again, after moving the handle a few times, and 
replace the cap nut. If the independent brake valve 
handle works hard, it should be similarly treated at this 
time, before opening the main reservoir and the brake 
valve cut-out cocks. 

If the handle latch becomes dry it will cause the 
handle to move over the notches with considerable resist- 
ance. A few drops of oil will remove this difficulty and 
permit the handle to move with proper freedom. 

If, with the handle in release, in running or in holding 
position, there is a constant leak at the brake pipe service 
exhaust, it indicates that the equalizing discharge valve 
is off its seat. By removing the exhaust plug and insert- 
ing a sharp piece of wood or by tapping while at the 
same time making a service application, the foreign 
matter will usually be dislodged and permit the valve to 
seat properly. 

The time required for the valve to discharge the equal- 
izing reservoir pressure should be carefully noted. To 
determine this, place the brake valve handle in service 



NO. 6 ET LOCOMOTIVE BRAKE. 239 

position. From a seventy-pound equalizing reservoir 
pressure it should take from six to seven seconds to 
reduce the pressure twenty pounds, and with no pounds 
pressure five to six seconds. 

A leaky rotary valve should be tested for by placing 
the brake valve handle in service position and allowing 
it to remain there until the brake pipe gauge pointer 
drops to zero, then close the brake valve cut-out cock 
and place the brake valve handle on lap. If a blow starts 
at the brake pipe exhaust, it indicates a leak through the 
rotary valve or the body gasket 19 into the brake pipe ; 
if an increase of pressure is noted on the equalizing 
reservoir gauge, it indicates a leak through the rotary 
or the body gasket 18 into the equalizing reservoir and 
chamber D ; if the brake cylinder pressure shows an 
increase or causes the safety valve to blow intermittently, 
•it indicates a leak past the rotary valve through the high 
speed supply port into the application cylinder of dis- 
tributing valve. 

INDEPENDENT BRAKE VALVE TEST. 

If the handle works hard it can be caused by a dry 
rotary valve or a dry rotary valve key gasket, the same 
as with the automatic brake valve, and the remedies 
prescribed for the automatic valve apply also to the 
independent valve ; however, should the handle continue 
to work hard after being properly oiled, it is likely that 
something is wrong with the return spring and its hous- 
ings, in which case an examination of these parts must 
be made to determine the trouble. If the return spring 
does not return the handle from release to running or 
from quick to- slow application position, the valve will 
have to be removed to examine it for the cause. 

A leaky rotary valve in the independent valve will 
cause the brake cylinder pressure to increase during a 



240 NO. 6 ET LOCOMOTIVE BRAKE. 

partial independent application to the limit of adjustment 
of the pressure reducing valve. 

DISTRIBUTING VALVE TEST. 

To test the distributing valve fpr excessive friction in 
the moving parts, after the system is fully charged, make 
a five-pound service reduction and note if brakes apply 
promptly. If they fail to apply it is caused by undue 
friction of application pistons and supply valve or of 
the equalizing slide valve and piston. 

If brakes apply properly, make a further five-pound 
reduction and note if cylinder pressure gradually 
increases beyond what it should be for a ten-pound reduc- 
tion, which is twenty-five pounds. If cylinder pressure 
increases it will most likely be caused by brake pipe 
reduction in pressure due to brake pipe leakage. 

A leak past the automatic rotary valve, the inde- 
pendent rotary valve, the equalizing slide valve or the 
graduating valve in the distributing valve will also cause 
the cylinder pressure to increase after a partial automatic 
service application ; if brake cylinder exhaust opens and 
closes intermittently it may be caused by supply valve 
leaking ; this is the case when the application chamber 
pressure remains constant. 

With no pounds brake pipe pressure it is not so easy 
to determine just the point where the leakage is occurring 
as it is with seventy oounds brake pipe pressure. With 
no pounds pressure the safety valve is set at a figure 
which is below the equalizing point of the pressure and 
application chambers ; therefore when testing the dis- 
tributing valve it is better to use seventy pounds brake 
pipe pressure. 

To determine the source of the leaks, with seventy 
pounds pressure, proceed as follows : After the brake 
application is made (ten pounds reduction), observe to 



NO. 6 ET LOCOMOTIVE BRAKE. 241 

what figure the brake cylinder pressure rises ; if it 
increases to fifty pounds and remains constant, it indi- 
cates brake pipe leakage (which always exists to a 
greater or lesser degree and therefore will eventually 
produce equalization), or a leak from the pressure cham- 
ber into the application chamber (it is generally assumed 
that if a rotary or slide valve leaks, they do so in all 
positions). 

If increase of brake cylinder pressure is due to leaky 
equalizing slide valve, release the brake and note if there 
is a leak at the direct exhaust of automatic brake valve 
when the handles of both brake valves are in running 
position ; this will determine if equalizing slide valve is 
tight. If graduating valve is leaking sufficiently to 
cause increase in the application chamber pressure after 
a partial service application and causes the equalizing 
slide valve and piston to move to release position, it will 
not release the locomotive brakes unless the engine is 
second in a double header with the automatic brake valve 
cut out. Leaky graduating valves, however, do not 
always cause equalizing piston and slide valve to move 
to release position, and when they do not, the application 
chamber pressure will usually increase to a point equal 
to the pressure chamber pressure and stop. If the brake 
cylinder pressure increases above adjustment of the 
safety valve, sixty-eight pounds, it is probable that the 
automatic rotary is leaking. If the brake cylinder pres- 
sure increases to forty-five pounds and stops, it is prob- 
able that the independent rotary leaks. 

If the brake releases after an automatic application, 
when the automatic brake valve handle is placed in 
release or in holding position, but remains applied after 
and independent application, it is caused by a leak from 
the distributing valve release pipe between the auto- 
matic and the independent brake valve. If the brake 



242' NO. 6 ET LOCOMOTIVE BRAKE. 

releases after an independent application, but remains 
applied with an automatic application, it is caused by a 
leak in the distributing valve release pipe between the 
distributing valve and the independent brake valve. 

If the brakes release after an automatic or an inde- 
pendent application, it is caused by a leak from the 
application cylinder pipe, application cylinder cap or 
gasket. 

A broken application piston graduating spring is indi- 
cated by a succession of quick exhausts from the brake 
cylinder exhaust. 

In cold weather the distributing valve should be 
drained by means of the drain cock. 

If the emergency valve in the quick action cap leaks 
it can be detected by a constant blow from the brake 
cylinder exhaust while the brakes are released, but to 
distinguish a leak through the emergency slide valve 
from one through the application slide valve, close cut- 
out cock in the supply pipe to the distributing valve. If 
the leak gradually ceases it is an application valve leak ; 
if it continues it is an emergency valve leak. 

To test a leaky check valve in the emergency cap, 
make continuous service application, reducing the 
brake pipe pressure about twenty pounds below the 
point of equalization, then close the brake valve cut-out 
cock and observe the brake pipe pressure gauge for an 
increase of pressure; if no increase is perceptible the 
check valve is tight. 

A weak or broken graduating spring is indicated by 
the equalizing piston and slide valve going to emergency 
position, when making partial service applications, and a 
quick rise in brake cylinder pressure to about sixty-five 
pounds. 



NO. 6 ET LOCOMOTIVE BRAKE. 243 

BRAKE CYLINDER LEAKAGE. 

Brake cylinder leakage can easily be determined with 
this equipment by the following method : Note the num- 
ber of strokes which the pump makes in a given period 
of time, then apply the brake with the independent brake 
valve, and after the pump has restored the main reservoir 
pressure again note the number of strokes which the 
pump makes. The difference in the number of strokes is 
a measure of the total leakage in all the brake cylinders. 

To determine which cylinder is leaking the most or 
rather how much each cylinder is leaking, after determin- 
ing the total leakage in the manner just described and 
with the brake still remaining applied, cut out the engine 
truck brake and note the number of pump strokes. 
Having done this, next cut out the driver brakes and 
note the number of pump strokes ; also the tender brake 
and note the number of strokes. The difference in the 
number of strokes indicates the amount of leakage in 
each cylinder. 

Another method of testing for brake cylinder leakage 
is to apply the brakes, then close the supply pipe cut-out 
cock and observe the reduction in cylinder pressure as 
registered on the brake cylinder gauge. By closing the 
various brake cylinder cut-out cocks as described in the 
preceding test, the amount of leakage in each brake 
cylinder can be closely determined. 

SAFETY VALVE. 

To test the safety valve, make an emergency applica- 
tion, leaving the automatic brake valve in emergency 
position, and note to what pressure the brake cylinder 
pressure rises before the safety valve opens. The adjust- 
ment of the safety valve should be sixty-eight pounds 
and it should not allow the pressure to rise above seventy. 



244 NO. 6 ET LOCOMOTIVE BRAKE. 

See that the safety valve cap is screwed down tightly 
in place and that all openings in the valve body are open 
and free from dirt. 

To test the pressure reducing valve for the inde- 
pendent brake valve, make a full independent brake 
application in quick application position. The brake 
cylinder pressure should not increase beyond forty-five 
pounds, and this amount should be obtained in from two 
to three seconds. In slow application position it should 
be from five to seven seconds. 

SIGNAL WHISTLE TEST. 

Examine all pipe joints and stop cocks in the signal 
piping system for leakage, and if any exists it should be 
stopped. The stop cocks in the end of the signal pipe 
should be carefully tested for leakage, as here is where 
leakage sometimes exists that causes the whistle to 
blow with the lone engine. Having made the signal line 
tight, if the whistle blows when an independent applica- 
tion of the brake is made, it is because of dirt on the 
non-return check valve in the combined check and 
strainer, or because of a leaky condition of this valve, or 
of the pressure reducing valve allowing signal line pres- 
sure to increase above forty-five pounds. 

A leak in signal line pressure should be made and 
the amount of fluctuation of the reducing valve noted. 
This fluctuation should not be greater than that recom- 
mended for the feed valve. An inspector's dummy coup- 
ling and test gauge should be used connected to signal 
hose in the rear. 

From the foregoing it will be seen that when the 
inspectors and enginemen become familiar with the prin- 
ciples of the equipment, they can easily figure out quick 
methods of testing it and apply the necessary remedies. 



THE NEW YORK AIR BRAKE 

AND 

SIGNAL SYSTEM. 

The following important parts of the New York Air 
Brake and Signal System differ from the corresponding 
parts of the Westinghouse System in its duplex air pump, 
governor, engineer's valve, compensating valve, quick 
action triple valve, air signal valve and train pipe strainer. 
The parts that are identical in both systems of equipment 
are as follows : The brake cylinders and pistons in all 
details, the main and auxiliary reservoirs, pressure retain- 
ing valves, reducing valves for the air signal system, 
brake pipe and hose couplings, angle and cut-Out cocks 
and conductor's valves. 

THE DUPLEX AIR PUMP. 

The No. 5 pump was designed and perfected to meet 
the demand for a pump that would furnish air for a 
freight train consisting of ioo cars and still be sufficiently 
within its capacity to reduce the liability of failure to a 
minimum. To meet these requirements such structural 
changes were made as were necessary to improve the 
design and increase the efficiency and economy of the 
duplex pump. 

Valve Gear. The valve gear of the duplex air pump 
is exceedingly simple, consisting of two ordinary D slide 

245 



246 NEW YORK DUPLEX AIR PUMP. 

valves, similar to the same type of valve used on loco- 
motives, actuated by valve stems which extend into the 
hollow piston rods of the steam cylinders, and are moved 
by contact with the tappet plates bolted on the steam 
piston heads. The valve on one side controls the admis- 
sion of steam to, and exhaust from, the opposite cylinder, 
so that while one of the pistons is moving the other is 
at rest. This feature also allows the air valves to seat by 
gravity. 

Air Cylinders. The air cylinders are known as the 
high and low pressure cylinders, and in each type of 
pump the difference in the areas of the air cylinders is in 
the same proportion, the low pressure having twice the 
area of the high pressure piston, and the latter having 
the same area as the steam cylinders. Thus three meas- 
ures of air are compressed with two measures of steam. 

Air Valves. The operation of all the duplex air 
pumps is practically the same, the difference being in the 
arrangement of the air valves. The No I and No. 2 have 
six air valves, viz : Upper and lower receiving, upper 
and lower intermediate, upper and lower discharge 
valves, and the same air inlets for both cylinders. The 
No. 5 and No. 6 pumps have separate air inlets for 
each cylinder and eight air valves, viz : Upper and lower 
receiving for low pressure cylinder, upper and lower 
intermediate, upper and lower receiving for high pressure 
cylinder and upper and lower discharge valves. The air 
valves of the No. 5 pump are alike in size and are inter- 
changeable. This is also true of the valves of the No. 
6 pump. 

The No. 5 and No. 6 pumps are identical except in 
size, and as this type of pump is the later one the opera- 
tion of the No. 5 will be described. 

Positions of Pistons. By referring to Figs. 96, 97, 98 
and 99 it will be seen that each part has a reference letter 



NEW YORK DUPLEX AIR PUMP. 



247 




Fig. 96. 

and that the pump pistons are shown in different posi- 
tions. Letters will be used in the description of the 
operation, so that the movements can easily be followed 
by referring to the plates when reading the explanation. 
Operation- Before the pump has been started, both 
pistons will naturally be at the bottom of the cylinders, 



248 NEW YORK DUPLEX AIR PUMP. 

due to their own weight, or, if not completely down, 
will at least have dropped enough to permit the slide 
valves to fall to the bottom of the steam chests. 

Assuming that the pistons are both down when the 
pump throttle is opened, live steam flows into both steam 
chests B, and is always present in them when the pump 
is taking steam. In this instance only, steam is admitted 
to both cylinders at once through port g to the upper 
side of piston H, which being at the bottom is merely 
held in that position, and through port o to the under 
side of piston T (Fig. 96). Piston T now moves upward 
and in doing so forces the air that is above the piston 
in low pressure cylinder D through intermediate valve K, 
into the high pressure cylinder F. At the same time 
the low pressure piston tends to create a vacuum under 
it, which is filled with air at atmospheric pressure 
through the air inlet at the right and receiving valve W. 
Just before piston T reaches the end of its upward stroke 
the tappet plate Q engages the button on the end of 
valve stem P, which moves slide valve C to its highest 
position, allowing the steam above piston H to pass 
through port g, cavity r in slide valve C and exhaust 
X to the atmosphere, and live steam through port s to 
the under side of piston H. As piston H moves upward 
(Fig. 97), the high pressure in cylinder F forces the air 
above it (which may be said to be in the first stage of 
compression) through discharge valve M to the main 
reservoir, while its upward movement tends to create 
a vacuum under it in the high pressure cylinder F, which 
is filled with air at atmospheric pressure through high 
pressure receiving valve N. 

Just before piston H completes its upward stroke 
(Fig. 98), tappet plate L engages with the button on the 
valve stem, raising it with slide valve A, exhausting the 
steam under piston T, through 0, cavity r in slide valve 



NEW YORK DUPLEX AIR PUMP. 



249 



A and exhaust X to the atmosphere, and admits steam 
through ports V to the upper side of piston T, moving 
it downward. During the downward movement of piston 




Fig. 97. 

T the low pressure piston in cylinder D forces the air 
under it, which was taken in on its upward stroke, 
through intermediate valve E to the under side of the 



250 



NEW YORK DUPLEX AIR PUMP. 




piston in high pressure cylinder F, and at the same time 
cylinder D is filled with air at atmospheric pressure 
through the air inlet and upper receiving valve U. Just 
before piston T completes its downward stroke (Fig. 
99), tappet plate Q, coming in contact with the lower 
tappet or shoulder on valve stem P, moves slide valve 



NEW YORK DUPLEX AIR PUMP. 



251 



C to its lowest position, allowing the steam under piston 
H to exhaust to the atmosphere through port s, cavity r 
in slide valve C and exhaust X, and admits live steam 
to the upper side of piston PI through port g, moving 
it downward. As piston H moves downward the high 
pressure piston forces the air under it through lower 




252 NEW YORK DUPLEX AIR PUMP. 

discharge valve I into the main reservoir, while the cylin- 
der is filled above with air at atmospheric pressure 
through the air inlet at the left and receiving valve J. 

The completion of this stroke completes one cycle 
of the pump. The movements described are repeated 
through each succeeding cycle. 

The air valves, through which air is being received 
or discharged during the movements of the pistons, are 
shown in the illustrations as being raised from their seats. 

Lubrication. The steam cylinders should receive a 
constant supply of oil from the lubricator (about one 
drop per minute), keeping all joints between the lubri- 
cator and the pump perfectly tight to prevent waste. Oil 
will leak away at the steam joints where there is little 
or nO indication of steam leakage. 

The piston rods should be kept well packed and good, 
clean, well-oiled swabs should be maintained on them. 

AUTOMATIC OIL CUP. 

Styles A and B of the automatic oil cup, which will 
lubricate an air cylinder at an even rate, are shown in 
Fig. loo. In the style A cup the quantity of oil fed to the 
air cylinder is governed by the diameter of the hole 
drilled in the feed cap OC 15, and can be regulated by 
changing the size of the hole or substituting a new 
piece drilled with a different size hole. Style B operates 
on the same plan and only differs from style A in that 
it has, in addition to the regulating ports in cap OC 14, 
an adjustable needle feed OC 17 for regulating the quan- 
tity of oil supplied. 

Operation. The principle of operation of the auto- 
matic oil cup is as follows : As the air piston makes its 
upward stroke compressed air is driven through the pas- 
sage drilled through the center post in the body of the 
oil cup, passes downward inside the extended sleeve of 



NEW YORK DUPLEX AIR PUMP. 



253 



the cap nut, and through the regulating ports drilled in 
this sleeve to the surface of the oil in the reservoir, on 
which it creates pressure. As the air piston makes its 
downward stroke a vacuum is formed in the passage in 
the center post and also inside the extended sleeve of 
the cap nut which envelops the center post, and the air- 
pressure on the surface of the oil, formed when the air 
piston made its upward or downward stroke, forces the 
oil to the inside of the sleeve and a small portion of it 



STYLE A 



STYLE B 




O.C.I 3 : 



Vi PIPE THD. 

Tig. 100 




o.c.ie 



THO 



is drawn into the air cylinder through the hole in the 
feed cap OC 15, or needle feed OC 17 which screws into 
the center post. 

The automatic oil cup supplies oil to the air cylinders 
only when the air pump is working, so that it performs 
the service required of it effectively, with the maximum 
economy in the use of oil. Its use will increase the life 
of the air cylinders, packing rings and piston rod pack- 
ing, as well as prevent hot pumps and the annoyance 
caused by the accumulation of gum in other parts of the 



254 NEW YORK DUPLEX AIR PUMP. 

engine equipment, due to the imperfect, wasteful and 
uneven lubrication of. the air cylinders heretofore in 
vogue. 

The oil cup should be filled before starting on a trip. 
Good cylinder oil should be used for this purpose, as 
other oils are not satisfactory for lubricating air cylinders 
on account of their low flashing point. The air pump 
should never be oiled through the air inlets, as it tends to 
gum and clog the valves and passages. The automatic 
cup can be filled whether the pump is running or. not, but 
it is a good plan to start the pump first, in order to be 
sure that the small port in feed cap OC 15 is open. Care 
should be exercised not to enlarge this port when clean- 
ing the oil cup. 

Starting the Pump. Before a pump is started the 
drain , cocks in the steam and exhaust passages should 
be opened. The steam valve should be opened slightly 
at first and the pump run very slowly until all the water 
of condensation has been worked out of the steam cylin- 
ders, and there is a pressure of 35 or 40 pounds accumu- 
lated in the main reservoir, as all locomotive air pumps 
depend on the air pressure in the main reservoir cushion- 
ing the air pistons to prevent them from striking the 
cylinder heads. If a pump is started at a high rate of 
speed the pistons will pound and become loose. 

Speed of Pump. The pump should be run at a rate 
of speed that is just sufficient to maintain the maximum 
pressure in the main reservoir and overcome the brake 
pipe leakage, and oil should be fcl to the cylinders 
according to the work they are doing. 

No more air should be compressed when the pump is 
run at a high speed than at a moderate one, as the air 
valves must have time to seat. The pump will do 
better work at a moderate speed of not over 60 double 
strokes per minute. 



NEW YORK DUPLEX AIR PUMP. 255 

Inspection. Before leaving the roundhouse with the 

- engine the engineman should know that the piston rod 

packing does not leak, that there are no unusual knocks 

or pounds, that the steam exhausts are regular and that 

the air compressing capacity of the pump is normal. 

DEFECTS OF THE DUPLEX AIR PUMP. 

. Pump Piston Rod Packing. If the piston rod packing 
blows out, the oil will be blown from the rod and swabs. 
If the air end of the high pressure rod packing leaks it 
will cut down the capacity of the pump, and the air 
cushion, which the pump should have to prevent the 
piston from striking the head, will escape. If it is the 
piston rod packing on the steam end that leaks it will 
permit a waste of steam from the steam cylinders and a 
large portion of this waste steam will be taken in at the 
lower air receiving valves, thus increasing the quantity 
of water which will accumulate in the main reservoir. 

Pump Pounding. If a pump pounds it is due to the loss 
of the air cushion at the completion of a stroke ; air 
cylinder packing leaking ; too high steam pressure and 
racing of pump ; loose reversing plates on the steam 
piston heads ; a badly worn button head on the end of 
valve stem ; the pump being loose on its bracket fasten- 
ings ; brackets loose on the boiler ; back leakage through 
the final discharge valve, or racing of the pump against 
low main reservoir pressure. 

Pump Stopping. When the pump stops of its own 
accord before maximum pressure has been attained the 
pump governor should be carefully examined to see that 
the relief port (the small port above the governor piston 
in the diaphragm body) is open. If a constant blow of 
air is found at this small port it indicates that the gov- 
ernor is at fault, and it should be examined and repaired. 

If the governor is in perfect order the steam head 



256 NEW YORK DUPLEX AIR PUMP. 

of the pump should be jarred slightly, and if this does 
not start the pump the air pump throttle should be closed, 
and the waste cock on the side of the steam chest of the 
pump opened, allowing all steam to escape, after which 
the pump throttle should again be opened. 

If,, after making the throttle test, the low pressure 
piston moves up and stops at the upper end of its stroke, 
and the high pressure piston refuses to move, the trouble 
should be looked for in the steam reversing gear on the 
right or low pressure side, as valve stem P may have 
become broken or reversing plate O become worn 
through. But if the high pressure and low pressure 
pistons move up, and the low pressure piston fails to 
move down, it indicates that the valve stem is broken, 
the reversing plate worn through on the high pressure 
side, or that the nuts on the air piston are loose, which 
would also prevent the pump from reversing. 

If the pump stops on account of a piston working 
off, the piston will strike hard on the air end. By remov- 
ing the oil cups the loose nut can be located by running 
a piece of wire through the oil cup. If the top head is 
removed the nut can be put back on the rod or removed 
entirely from the cylinder. 

Sometimes a pump will stop for want of sufficient 
lubrication, and when this occurs it can be started by 
shutting off the steam for a few moments, opening the 
drain cock in the steam passage and again turning on 
the steam, regulating the lubricator to feed a few extra 
drops of oil. If this does not overcome the difficulty 
it is probably due to a breakage, which will have to be 
repaired in the shop or roundhouse, as engines are not 
usually provided with the tools and necessary parts to 
make such repairs on the road. 

Uneven Exhausts. If the exhausts are irregular it is 
due to the leakage of air from the main reservoir back 



NEW YORK DUPLEX AIR PUMP. 257 

into the high pressure cylinder, leakage from the high 
pressure to the low pressure cylinder, or an air valve stuck 
to its seat. 

When the exhaust sounds in two pairs, one pair 
spaced well apart and the other pair very close together, 
it indicates that an intermediate air valve (E K) or a 
cylinder head gasket is leaking at a point between two 
cylinders. This would permit the air from the high 
pressure cylinder to pass over into the low pressure cyl- 
inder instead of being forced into the main reservoir. As 
a result, when the low pressure piston takes steam it 
has both steam and air pressures to cause it to make a 
quick stroke, which brings two steam exhausts very close 
together. 

When the spaces between three exhausts are nearly 
equal and those between the third and fourth exhausts 
are very long it indicates that a discharge valve is broken, 
the upper air cylinder gasket is leaking badly between 
the final discharge valve cavity and the air cylinder, or 
that the lower intermediate valve seat is loose and has 
worked up sufficiently to raise the intermediate air valve 
against its seat. 

If either of the steam piston heads- becomes discon- 
nected from the rod it will cause a stoppage of the pump. 
This trouble will be indicated by a hard steam blow at 
the exhaust, making the same sound as a blower turned 
on full. 

Leakages. Back leakage from the low pressure air 
cylinder through the air inlet valve can be tested for by 
holding the hand over the strainer while the low pres- 
sure piston is moving toward either receiving valve ; if 
they leak, air will blow past them to the atmosphere at 
the strainer. 

Leakage past intermediate valves E and K can be 
detected by the earlier movement of the low pressure 



258 NEW YORK DUPLEX AIR PUMP. 

piston away from the defective valve, and the weak 
intake of air at the inlet valves U or W (upper or lower), 
as the case may be, and also by the heating of the pump. 

Leakage past the final discharge valves M and I in 
the high pressure cylinder can be detected by the slower 
movement of both the low and the high pressure pistons 
toward the leaky valve, and the quicker movement of the 
high pressure piston away from it. 

To test for worn piston packing rings the pump 
should be run at a moderate speed against the maximum 
main reservoir pressure. If, on either the up or down 
stroke, air is drawn in lightly for the first part of the 
stroke and the suction ceases as the piston nears the 
end of its stroke, it indicates a leakage past the packing 
rings. To locate the defective piston it should be noted 
which one in making its stroke fails to draw in air 
properly. Leaky rings in the high pressure cylinder can 
be located in the same manner. 

Blozvs. A blow will occur in the steam end of the pump 
if the ends of the reversing rods in the cap nuts are 
worn, the main slide valve or its seat cut or defective so 
that steam can escape to the exhaust passage, the pack- 
ing rings in the steam piston worn or broken, or the 
cylinder worn. 

If the tapped rods are worn so that steam can pass 
through them into the cap nuts it will return through the 
passage drilled in the rods to the lower end of the steam 
cylinder and cause a blow in the lower end of the piston 
in which it is working. If the slide valves or their seats 
are leaking or cut, steam can escape through the slide 
valve chamber into the exhaust, and a constant blow will 
be produced. If the packing rings on the steam piston 
are worn or broken, steam will pass by them from one 
side to the other and escape through the exhaust opening. 

Pump Heating. If the pump runs hot it is due to a 



NEW YORK DUPLEX AIR PUMP. 259 

leak past the piston rod packing, a leaky intermediate 
discharge valve, leaky receiving valves, badly worn pack- 
ing rings in the air end, or racing the pump under high 
steam pressure. 

To cool the pump a small quantity of valve oil should 
be used in the high pressure air cylinder, and if the pres- 
sure can be maintained the pump should be run slowly 
until cooled. 



2<5o NEW YORK AIR PUMP GOVERNORS. 



NEW YORK AIR PUMP GOVERNORS. 

STYLE "C" PUMP GOVERNOR. 

The function of the pump governor is to stop the 
pump when the maximum pressure has been attained 



T 









~& Copper P ipe 
* Air Connection 



i 



r>.jco 



I I DP 58 

PG 38 

I DP 59. 

' T'Pipe 
I to Steam 
V V alve 




To 



Air Pump 



Fits Nut 
2 DP 56 



and to allow steam to be again admitted when this pres- 
sure has been slightly reduced, thus maintaining prac- 
tically a constant pressure. 



NEW YORK AIR PUMP GOVERNORS. 261 



The pump governor is shown with the steam valve 
open in Fig. 101, and closed in Fig. 102; the arrows 
indicate the direction of the flow of steam and air. 

Operation. When sufficient air pressure, the amount 
for which the governor is adjusted, accumulates in the 

h— - — :: 3— ~ 

PG 34 

PG 35 




7WyyyAyyyy/A 

Fig. 102. 



Fits Nut 
i 2 DP 56 



diaphragm air valve chamber to overcome the resistance 
of regulating spring PG 10, the diaphragm air valve PG 
13 is lifted, uncovering the air passage in its seat PG 14, 
and air flows down on top of piston PG 4, which rests on 



2-62 NEW YORK AIR PUMP GOVERNORS. 

top of steam valve PG 5 ; then the piston and steam valve 
together are forced downward until the steam valve 
seats, as shown in Fig. 102, and closes the steam passage 
leading to the air pump, thus cutting off the supply of 
steam. This action takes place when the air pressure for 
which the governor is adjusted has been obtained. 

When the air pressure in the diphragm air chamber 
falls below the tension of the regulating spring, dia- 
phragm air valve PG 13 seats, as shown in Fig. 101, and 
cuts off the flow of air to governor piston PG 4. 

The remaining air pressure in the governor piston 
chamber is quickly reduced by escaping through the small 
vent. port, indicated by the small dotted circles., in the 
air passage connecting the diaphragm air valve and the 
governor piston air chambers ; then the steam pressure 
acting upwardly on the face of steam valve PG 5 forces 
this valve open and admits steam to the pump. 

DUPLEX PUMP GOVERNOR. 

The duplex pump governor (Fig. 103) differs in 
construction from the single governor in that it has two 
pressure tops connected by means of a "siamese" fitting 
to a single body. It is used for the single pressure 
system, the same as the single governor, and also for 
what is known as the double pressure, or high pressure 
control system 

Adjustment. The pump governor is adjusted to 
regulate the amount of air pressure carried by means of 
regulating spring PG 10. By screwing down adjusting 
nut PG 35, the tension of this spring is increased, and 
by screwing up the nut it is decreased. 

Increasing the tension of the spring increases the air 
pressure that may be carried, and decreasing the tension 
decreases the- pressure. 



NEW YORK AIR PUMP GOVERNORS. 263 

The adjusting nut should be screwed down until the 
pump stops at the desired pressure, and the promptness 
with which the pump starts when the air pressure reduces 
should be noted. If the pump does not start promptly 



«*r Copper 



>ipe 




l"Pipe 

To Steam 

Valve 



Fig. 103. 



the adjusting nut should be screwed up a trifle and again 
screwed down if the required pressure is not maintained, 
after which the cap nut should be replaced securely. 

When adjusting the pump governor care should be 
taken to ascertain that the air gauge is correct. Often 
when trouble is experienced in adjusting governors the 
trouble is due to the erratic action of the air gauge. 



264 NEW YORK AIR PUMP GOVERNORS. 

DEFECTS OF THE PUMP GOVERNOR. 

If the governor has been properly adjusted and, without 
any change of adjustment, gradually increases the amount 
of pressure, the trouble is probably due to the accumulation 
of gum on the face of the diaphragm air valve PG 13, where 
it seats over the air passage PG 14, thereby increasing the 
length of the port and reducing the lift of the diaphragm. 

The following defects will not allow the governor to 
shut off the steam when the maximum air pressure is 
obtained : The regulating spring may be adjusted too 
tightly ; too much oil used in the air end of the pump, caus- 
ing the valve to gum up on its seat ; air leaking by the gover- 
nor piston as fast as it passes into the passage over the 
piston ; the governor piston sticking so that the air pressure 
cannot force the piston down. If the waste pipe in the steam 
end of the governor is stopped up so that steam or air 
accumulates below the piston the governor will not shut off 
at any pressure, and if there is a leak by the diaphragm with 
the hole in the spring casing stopped up it will prevent the 
governor from operating. 

If the governor stops the pump and fails to release it 
promptly, when the air pressure in the main drum has been 
reduced sufficiently, it indicates a leakage past the dia- 
phragm air valve, permitting air to flow down onto the 
governor piston, which would tend to hold the steam valve 
closed and would prevent it from opening promptly. This 
defect is indicated by a constant flow of air from the small 
relief port in the diaphragm body above the governor piston. 

When the governor is correctly adjusted, and it fails to 
reduce the speed of the pump when the standard pressure 
has been accumulated, it may be due to the closing of the 
lower drainage port leading from the under side of the 
governor piston to the atmosphere, the diaphragm air valve 
leaking around its edge into the spring casing with the relief 



NEW YORK AIR PUMP GOVERNORS. 265 

port in the casing clogged, or the port leading from the dia- 
phragm seat to the top of the governor piston closed with 
gum. The accumulation of gum at this point is caused by 
dirt and other foreign matter finding its way into the gover- 
nor and lodging on the seat of the diaphragm valve. Exces- 
sive quantities of poor oil used in the air cylinders and 
pumps that run hot also contribute to the accumulation of 
gum at this point. 



266 B3 LOCOMOTIVE BRAKE EQUIPMENT. 



THE B3 LOCOMOTIVE BRAKE EQUIPMENT. 

The locomotive brake equipment described and illus- 
trated herein is known as the B3 equipment, and is arranged 
in four different schedules to cover the general requirements 
of railroad service. 

Schedule B3 is for engines in passenger or freight serv- 
ice where but one brake pipe pressure is used. Both the 
pump governor and the pressure controller have single regu- 
lating heads, which should be adjusted for the standard 
brake pipe and main reservoir pressures (Plate 14, Fig. 1). 

Schedule B3-S is for switch engines only. A single 
pump governor and a single pressure controller are used. 
The controller is set to give a brake pipe pressure of 70 
pounds and the pump governor for 90 pounds main reser- 
voir pressure for ordinary switching service. However, 
when the engine is used for passenger switching service, 
and handles trains that are using no pounds brake pipe 
pressure, the pump governor should be adjusted to no 
pounds main reservoir pressure. When handling trains 
using high pressure, cock No. 2 between the regulating 
and supply parts of the controller should be closed. This 
renders the controller inoperative and allows the main reser- 
voir pressure of no pounds to pass to the brake valve and 
brake pipe, so that trains using the high speed brake can 
be handled without delay and without the necessity of addi- 
tional apparatus. A quick release valve is furnished with 
this schedule and is to be placed in the straight air pipe so 
that the brakes can be released quickly, permitting quicker 
movement. The divided reservoir and the accelerator valve 
are not furnished with this schedule. The supplementary 
reservoir is substituted for the divided reservoir (Plate 14, 
Fig. 2). 

Schedule B3-HP is for freight service where heavily 




3 AN 





PLATE 14. FIGURES 1, 2, 3 AND 4 









' 



B 3 LOCOMOTIVE BRAKE EQUIPMENT. 267 

loaded trains are handled on heavy grades, or loads handled 
down grades and empties up grade. Both regulating por- 
tions of the pump governor and the pressure controller are 
duplex, so that pressures of 70 and 90 pounds can be car- 
ried in the brake pipe, and 90 and no pounds in the main 
reservoir, for the ordinary brake pipe pressure and the high 
pressure control. 

Three-way cocks are provided for the operation of these 
duplex regulating parts, being connected as shown in the 
piping diagram (Plate 14, Fig. 3). To operate these cocks 
the handle should be turned in line with the pipe line leading 
to the regulating head to be used, high or low pressure, as 
desired. This will cut in the head to regulate the supply' 
portion and cut off the pressure to the one not in use. 

Schedule B3-HS is the high speed brake. It includes 
the duplex pressure controller and the duplex pump gover- 
nor. The regulating heads of the pressure controller should 
be adjusted to 70 and no pounds for brake pipe pressure, 
and the pump governor heads adjusted to 90 and 130 
pounds for main reservoir pressure. A union four-way 
cock is used with the regulating heads of the pressure con- 
troller. This is a special cock with a connection to each 
regulating top, one to the supply pipe between the controller 
and brake valve and one to the pipe connecting the brake 
valve and accelerator reservoir. When the handle of the 
four-way cock is in position to operate the regulating head 
adjusted to no pounds brake pipe pressure, a small port in 
the accelerator reservoir connection is brought into com- 
munication with a port to the atmosphere. The object of 
this port is to prevent more than the usual predetermined 
reduction of brake pipe air obtained in the graduating 
notches taking place with no pounds pressure. A union 
three-way cock connected to the main reservoir and pump 
governor regulating tops is used to change the main reser- 
voir pressure (Plate 14, Fig. 4). 



268 B3 LOCOMOTIVE BRAKE EQUIPMENT. 

Piping Diagrams. Plate 14, Figs. 104, 105, 106 and 
107 show the piping diagrams of the four schedules of the 
B3 equipment, and also the several parts comprising each 
schedule, as well as the proper pipe connections. This 
equipment is an improvement over former equipments. It 
not only includes all necessary features for the automatic 
brake, but also a straight air brake for the locomotive and 
tender, all operated by the automatic brake valve without 
any additional positions. 

Improvements in the B3 Brake Valve. Among the 
improvements incorporated in the B3 brake valve are, the 
use of tap bolts instead of screws to fasten the valve cover 
to the body, and port O is cored in the valve body instead of 
being drilled through the cover. The projection for center- 
ing the piston packing leather EV 107 is on the piston 
instead of on the follower. A new packing leather can 
therefore be applied without removing the piston from the 
brake valve, it only being necessary to remove the black 
cap and the piston follower. 

Other parts of the equipment fully described under their 
different headings are: The 1^4-inch pressure controller, 
by which the brake pipe pressure is regulated ; the acceler- 
ator valve, which assists the brake valve in discharging 
brake pipe air when making service applications with long 
trains ; the %-inch controller, which controls the straight 
air brake pressure ; the high speed controller, which acts as 
a reducing valve for the driver and truck brake cylinders ; 
the lever safety valve, and the quick release valve. 

MANIPULATION. 

To apply the automatic brakes on the locomotive and 
train, the handle of the brake valve should be moved to the 
graduating notch necessary to make the desired brake pipe 
reduction. 

To release both locomotive and train brakes, the handle 



B 3 LOCOMOTIVE BRAKE EQUIPMENT. 269 

should be moved to running and straight air release position. 

To release the train brakes and hold the locomotive 
brakes set, the handle should be moved to automatic release 
and straight air application position. 

'To apply the locomotive brakes (straight air), the handle 
should be moved to full automatic release and straight air 
application position. 

To release the locomotive brakes, the handle should be 
moved to running and straight air release position. 

To apply the brakes in an emergency, the handle should 
be moved quickly to emergency position and left there 
until the train stops. 

In case the automatic brakes are applied by the bursting 
of a hose, the train parting, or the conductor's valve is 
opened, the handle should be placed in lap position in order 
to retain the main reservoir pressure. 

To graduate off or entirely release the locomotive brakes 
zvhile holding the train brakes applied, the lever safety valve 
should be used to make the required reduction. 

The handle of the brake valve will be found to work 
freely and easily at all times, as the pressure on the main 
slide valve does not exceed the maximum brake pipe pres- 
sure. 

The cylinder gauge will show at all times the pressure 
in the locomotive brake cylinder and should be observed in 
brake manipulations. 

Double-Heading. 'When there are two or more loco- 
motives in a train, cut-out cock No. 1 should be turned 
to close the brake pipe and the brake valve carried in 
running and straight air release position on all locomo- 
tives, except the one from which the brakes are operated. 

Cutting Out the Straight Air Brake. If it becomes 
necessary to cue out the straight air brake, cut-out cock 
No. 3, located in the straight air pipe, should be closed. 

Cutting Out the Automatic Brake on the Engine. To 



270 B3 LOCOMOTIVE BRAKE EQUIPMENT. 

cut out the automatic brake on the engine, cut-out cock 
No. 6, located in the pipe connecting the triple valve and 
the double check valve, should be closed. By locating 
the cut-out cock at this point the auxiliary reservoir wili 
remain charged if the brake is cut out, and it can be cut 
in immediately if so desired. This cut-out cock and also 
cut-out cock No. 3 are special ; they are of the three-way- 
pattern and when turned off drain the pipes leading to 
the double check valve, which insures the check valve 
remaining seated in the direction of the closed cock. 

Cut-Oujt Cock No. 4. Main reservoir cock No. 4 is for 
the purpose of cutting off the supply of air when remov- 
ing any of the apparatus, except the governor. 

Straight Air Controller. The function of the straight 
air controller is to limit the pressure in the driver, truck 
and tender brake cylinders for the straight air brakes. It 
should be adjusted to withstand a pressure of 40 pounds. 

THE B3 BRAKE VALVE. 

List of Parts. Figs. 108, 109, 110 and in show the dif- 
ferent parts of the brake valve as follows : 



QT 3. Piston Ring. 

QT 29. 1 -inch Union Bolt. 

QT 30. 1 -inch Union Swivel 

QT 31. 1 -inch Union Gasket 

EV 60. Small Union Nut. 

EV 75. Handle Pin. 

EV yy. Handle Set Screw. 

EV 96. ^-inch Plug. 

EV 103. End Plug. 

EV 107. Packing Leather. 

EV 108. Expander. 



EV in. Graduating Valve 
Spring. 

EV 113. Fulcrum Pin. 

EV 121. Lever Shaft Pack- 
ing. 

EV 1 23B. Handle. 

EV 128. Small Union Stud. 

EV 158. Union Swivel. 

EV 165. Lever Shaft Nut. 

EV 172. Quadrant Latch. 

EV 173. Latch Screw. 



B3 LOCOMOTIVE BRAKE EQUIPMENT. 271 



EV 175. Link Pin Cotter. 

EV 180. Vent Valve. 

EV 181. Follow Cap Nut. 

EV 182. Vent Valve Spring. 

EV 183. Piston Cotter. 

EV 192. Cap Gasket. 

EV 196. Lever Shaft Plug. 

EV 199. Back Cap Stud and 

Nut. 

EV 301. Follower. 

EV 302. Graduating Valve 

Lever. 

EV 303. Link. 

EV 304. Slide Valve Lever. 

EV 305. Lever Shaft. 



EV 306. 
EV 307. 
EV 309. 
EV 310. 
EV311. 
EV 312. 
EV313. 

EV314. 
EV 315. 
EV316. 
EV317. 
EV 323. 
EV 325. 
EV610. 



Quadrant Screw. 
Cover Gasket. 
Body. 
Back Cap. 
Piston. 

Main Slide Valve. 
Valve Cover 
Quadrant. 
Cover Bolt. 
Link Pin. 
Graduating Valve. 
Nut Lock Bolt. 
Nut Lock Spring. 
Handle Spring. 



Fig. 108 is a longitudinal side section of the brake 
valve (running position), showing the main slide valve 
EV 312 and how the graduating valve EV 317 is con- 
trolled by piston EV311 and lever EV 302 ; also port O 
in the back cap, closed by the vent valve EV 180. This 
view also shows the different positions of the brake valve 
handle. Fig. 109 is a cross section through the valve 
(rear view). Fig. no is a cross section through the main 
slide valve EV 312. This view shows the main reservoir 
and brake pipe connections ; it also shows the location of 
passage H, which connects the supplementary reservoir 
and chamber D, back of piston EV 311; also port O 
drilled to the slide valve seat, and cavity R in the slide 
valve. Fig. in is a top view of the valve with the cover, 
slide valve and handle removed, showing the seat and 
connections for the straight air and divided reservoir 
pipes. A shows the opening through the 'slide valve seat 
to brake valve chamber A beneath the slide valve ; B is 
a cavitv back of the slide valve seat into which the air 



272 B3 LOCOMOTIVE BRAKE EQUIPMENT. 

flows from the main reservoir pipe, although all the space 
under the valve cover and above the slide valve is known 
as chamber B ; G is the exhaust passage ; V is a port in 
the seat through to the exhaust passage and is an 
exhaust port for the straight air brake in running and 
straight air release positions, and is also an exhaust port 




EV307 
EV60 
EVI58 

g" COPPER PIPE 
TO ACCELERATOR 
RESERVOIR 



Fig. 108. 

for the air from chamber D through port O in the release, 
running and lap positions ; port T leads to the accelerator 
reservoir; port W leads to passage H and the supple- 
mentary reservoir. The location of port O in the seat 
is also shown. 



B 3 LOCOMOTIVE BRAKE EQUIPMENT. 273 

Port O is used for the purpose of venting air from 
chamber D to the atmosphere, so as to permit piston 
EV 311 to return to its normal position (Fig. 108) when 
releasing brakes. It runs from the vent valve seat 
through the back cap, lengthwise through the body of the 
brake valve to a point shown in Fig. 109 and thence up 




Fig. 109. 



to the seat of the slide valve. It is connected to the 
exhaust passage by cavity R in the slide valve and port 
V in the seat in full release, running and lap positions. 
Chamber D air is prevented from escaping to the 
atmosphere in these positions by vent valve EV 180 on 



274 B3 LOCOMOTIVE BRAKE EQUIPMENT. 

the end of piston EV311. Just before the slide valve 
reaches the first graduating notch it covers port O, so 
that when the piston moves forward to automatically 
close the service exhaust port F, chamber D air only 
gets to the face of the slide valve. When the brake valve 
is placed in full release, running or lap position, air from 




I PIPE f PIPE 

TO BRAKE PIPE TO MAIN RESERVOIR 



Fig. 110. 



chamber D flows through port O, cavity R and port V 
to the atmosphere, until the pressure in chamber D is 
slightly below that in chamber A (brake pipe), when the 
brake pipe pressure, being the greater, forces piston EV 
311 to the position shown in Fig. 108, seating the vent 



B 3 LOCOMOTIVE BRAKE EQUIPMENT. 275 



valve and preventing further escape of air from cham- 
ber D. 

Pipe Connections. EV 326 is a pipe bracket bolted to 
the side of the brake valve. It has two pipe connections, 
one to the main reservoir and the other to the brake 
cylinders. Dotted lines show the cored passage from the 
main reservoir connections to port N, and from port E 
to the cylinder pipe connection. 

Slide Valve. Fig. 112 shows the face of the slide 
valve. F and G are the service exhaust ports, and are 
connected by a passage through the center of the slide 
valve ; J and K are the emergency exhaust ports con- 
nected by passages on each side of the central passage 
connecting F and G ; S is a small port connected by pas- 
sage X to the elongated port Ac, which registers with port 




• TO SUPPLEMENTARY 
RESERVOIR 



Fig. 111. 



T in the seat in all the service application positions ; P is 
a groove and its function is to connect port \Y and the 
supplementary reservoir with brake pipe pressure in 
release and running positions ; L is a passage through 
which air passes from the main reservoir pipe to the 
brake cylinder pipe in a straight air application position ; 
R is a cavity connecting ports E and V in running and 
straight air release positions to release the straight air 
brakes, and connects ports O and V in release, running 
and lap positions. 



276 B 3 LOCOMOTIVE BRAKE EQUIPMENT. 

It also permits the partial opening of port N to E in 
the last graduating notch and full opening in emergency 
position. Ports M are through the slide valve and are 
for the purpose of charging the brake pipe. 

Course of Main Reservoir and Brake Pipe Air. Main 
reservoir air, reduced to brake pipe pressure by the pres- 
sure controller, flows into chamber B. The slide valve 
EV 312 controls the flow of air from the main reservoir 
to the brake pipe and from the brake pipe to the atmos- 
phere. The brake pipe is connected to chamber A. Dis- 




F S J X A< 

Fig. 112. 



charge of brake pipe air to the atmosphere for service 
applications occurs through ports F and G and exhaust 
passage C, but, for emergency application, through ports 
J and K and exhaust passage C. In full automatic release 
position, air is free to flow from the main reservoir to the 
brake pipe through ports M and past the end of slide 
valve EV 312. In running position* ports M only are 
open between the main reservoir and the brake pipe, but 
they are sufficiently large to permit the release of the 
train brakes. Small slide valve EV 317 'is a cut-off or 
graduating valve, operated* by piston EV311 and lever 
EV 302. In service applications it automatically laps 
port F and stops the discharge of brake pipe air, when 
the brake pipe reduction, corresponding to the service 
graduating notch in which the handle is placed, has been 
made. Piston EV311, which is exposed on one side to 



B3 LOCOMOTIVE BRAKE EQUIPMENT. 277 

brake pipe pressure and on the other to chamber D or 
supplementary reservoir pressure, through the agency of 
lever EV 302, causes valve EV 317 to move automatically 
whatever distance is necessary to close port F. 

Automatic Release and Straight Air Application Posi- 
tion. Fig. 113 shows automatic release and straight air 
application position. The purpose of this position is to 
promptly release the automatic brakes and to apply the 
straight air brakes or retain the pressure in the locomo- 
tive and tender brake cylinders. In this position air flows 
directly from chamber B (main reservoir) into chamber 
A (brake pipe), past the end of the slide valve and 
through ports M. Port O is open to the atmosphere 
through port V to permit piston EV311 to return to its 
normal position. Port T is open to the atmosphere 
through j and C. The supplementary reservoir is being 



A F S C T J X Ac 




W N I E V J 

Fig. 113. 

charged to brake pipe pressure through groove P and 
port W from chamber A. Port E is brought into com- 
munication with port N by passage L, permitting air to 
pass to the locomotive and tender brake cylinders, 
through the straight air pipe and double check valve, 
until shut off by the 34-inch pressure controller, the regu- 
lating top of which is connected to the straight air pipe 
and is adjusted at 40 pounds. By placing the valve 



278 B 3 LOCOMOTIVE BRAKE EQUIPMENT. 

handle about midway between release and running posi- 
tions the straight air ports can be lapped, making it possi- 
ble to increase or decrease the brake cylinder pressure 
as may be desired. 

Running and Straight Air Release Position. Fig. 
114 shows the running and straight air release position. 
This is the position in which to place the handle when 
wishing to release the train and locomotive brakes simul- 
taneously, or to release the straight air brake when it 
only has been applied. Air passes from the main reser- 
voir to the brake pipe through ports M. Port N is closed ; 
port E is brought into communication with port.V and 



A F S J C T X Ac 




the atmosphere by cavity R, releasing the straight air 
brake ; ports O and T are still open to the atmosphere as 
in full release position; port T is open to the atmosphere 
through J and C in release and running positions, so that 
in case of a release, following a partial application, the 
accelerator reservoir pressure can escape and prevent the 
operation of the accelerator valve, while groove P still 
holds port W in communication with the brake pipe 
pressure in chamber A. 

Lap Position. Fig. 115 shows lap position. The 
brake valve handle should be placed in this position when 
a hose bursts, a train parts or a conductor's valve is open, 



B 3 LOCOMOTIVE BRAKE EQUIPMENT. 279 



for the purpose of saving the main reservoir air. All 
ports are closed in this position, except port O, which is 
open to the atmosphere through port V and the exhaust 
passage in leiease, running and lap positions. 




Service Application. Fig. 116 shows service applica- 
tion position. This position is for the purpose of gradu- 
ally applying the brakes, and is divided into five gradu- 
ating positions designated by notches on the quadrant. 
The reduction in brake pipe pressure obtained in the dif- 




W L 



N J E R V 

Fig. 116. 



ferent notches are respectively 5, 8, 11, 15 and 23 pounds. 
The amount of the initial reduction should always be 
governed by the length of the train, speeds, grades, etc. 
The handle of the brake valve should always be placed 
in the notch which will give the required reduction. 



28o B3 LOCOMOTIVE BRAKE EQUIPMENT. 



When the brake valve is moved to the first graduating 
notch the slide valve is in the position shown. Port O 
is closed to prevent the escape of chamber D pressure ; 
port F is moved back of the graduating valve "EV 317, 
and port G registers with exhaust port C. Brake pipe air 
now flows to the atmosphere. It also flows through port 
S, passage X and port T to the accelerator reservoir, 
building up a pressure to operate the accelerator valve. 
As soon as the pressure in the brake pipe reduces, the 
pressure in chamber D, now being the greater, begins to 
expand to equalize with the brake pipe pressure, and in 
doing so moves piston EV 311 forward. The piston car- 
ries with it the lower end of the graduating" valve lever 




W N J R 

Fig. 117. 

EV 302, which is so proportioned that the graduating 
valve EV 317 on the other end of it is moved back just 
far enough to close ports F and S when the pressures in 
chamber D and the brake pipe have equalized. This 
stops the flow of air from the brake pipe to the atmos- 
phere and to the accelerator reservoir. This action is 
called automatic lap, and it takes place in all the gradu- 
ating positions. A further reduction of the brake pipe 
pressure is made by moving the brake valve handle back 
to any of the service notches, the piston moving further 
forward for each successive reduction. The action of the 
brake valve is the same and the ports are in the same rela- 



B3 LOCOMOTIVE BRAKE EQUIPMENT. 281 

tion to each other in all service positions of the brake 
valve, except the last graduating position, shown in Fig. 
117. In this position a partial opening of port N admits 
air slowly to the locomotive and tender brake cylinders, 
through cavity R and port E, up to the adjustment of 
the controller on the straight air pipe, which will insure 
full braking p: essure on the engine with a full applica- 
tion, regardless of piston travel and brake cylinder leak- 
age. 

Emergency Application. Fig. 118 shows emergency 
application position. This position is for the purpose of 
producing a quick, heavy reduction in brake pipe pressure 



F S J A X Ac C T 




so that all the triple valves on the train will operate in 
quick action and apply the brakes in the shortest possible 
time. Port J registers with chamber A, and K with the 
exhaust port C, allowing brake pipe air to escape rapidly 
to the atmosphere. Cavity R allows air from the main 
reservoir to pass through ports N and E to the locomo- 
tive brake cylinders, and the full pressure of the straight 
air brake is maintained on the engine. 

DEFECTS OF THE B3 BRAKE VALVE. 

To test for a main slide valve leak the cut-out cock 
below the brake valve should be closed, the pump started, 



282 B 3 LOCOMOTIVE BRAKE EQUIPMENT. 

and the brake valve handle placed in lap position. All 
ports are then blanked and any leakage past the slide 
valve to the brake pipe will be indicated by the black 
hand of the air gauge. Another method of making this 
test is to make a full service application when the brake 
system is charged. This reduction would cause a differ- 
ence between the brake pipe pressure and that on top of 
the slide valve, and if there were any leak by the slide 
valve it would be indicated by the brake releasing and 
the raising of the black hand of the air gauge. Still 
another method of testing would be to place the brake 
valve in either graduating notch when the brake system 
is charged, and if the escape of air at exhaust passage C 
did not entirely stop and the black hand of the air gauge 
did not fall at the same time, it would indicate that the 
main slide valve was leaking. 

To test for a leaky graduating valve, after the brake 
system is fully charged, the brake valve should be placed 
in the first graduating notch. If the blow continues at 
exhaust port C, venting the air from the brake pipe to 
the atmosphere, it indicates a leaky graduating valve. 

If the packing ring on the equalizing piston leaks it 
can be detected by having the full pressure in the brake 
system, turning the cut-out cock below the brake valve 
and placing the brake valve in emergency position. If 
air escapes from port C until the supplementary reservoir 
is drained, it indicates a leak at the packing ring. 

If the vent valve leaks it will be indicated by a con- 
stant blow from exhaust port C when the brake valve is 
in full release, running or lap position. 

SUPPLEMENTARY RESERVOIR. 

Fig. 119 shows a supplementary reservoir used with 
switch engine equipment, schedule B3-S. The names of 
the parts are: EV 60, Small Union Nut; EV 155, Sup- 



B 3 LOCOMOTIVE BRAKE EQUIPMENT. 283 

plementary Reservoir; EV 156, Reservoir Plug; EV 158, 
Union Swivel. 

The duty of the supplementary reservoir in service 
application is to hold the air used to move the equalizing- 
piston and graduating valve, and automatically lap the 
valve in service reductions. Any leakage in the supple- 
mentary reservoir or pipe connection, or gasket EV 107, 
destroys this feature and renders it necessary to place the 
brake valve handle in lap position after each reduction to 
prevent all brake pipe air from being lost. 

If there is a broken pipe connection leading to the 
supplementary reservoir it would be necessary to put in 



— rft 



3 ii"«- 



Jbolt 



5KU.1N. 

. CAPACITY 



Xr: 



D 



-* 



ETVioo 
EVI56 
EV60 

evi5 




3 



zzzry 



J COPPER PIPE 
TO BRAKE VALVE, 



Fig. 119. 

a blind gasket between the brake pipe and the joint, and 
place the brake valve handle in lap position after each 
reduction. 



DIVIDED RESERVOIR. 

Fig. 120 shows the divided reservoir (side and end 
view) used with schedule B2 and B3. When the accel- 
erator valve is being used, the small compartment is used 
for chamber D pressure and the large compartment for 



284 B3 LOCOMOTIVE BRAKE EQUIPMENT. 

the use of the accelerator valve. The end view shows 
where the accelerator valve is attached. 




EV60-^lJ> 

E V62— -~^— 3® 



RVI34 
RVI4 



Fig. 120. 



EV200 




PRESSURE CONTROLLER. 



The pressure controller is in reality a part of the 
brake valve, taking the place of the excess pressure or 
feed valve, and is connected to the main reservoir pipe 
near the brake valve for the purpose of controlling the 
brake pipe pressure. The regulating and supply por- 
tions are separate, being connected by piping, and the 
regulating heads connect directly to the pipe between 
the supply portion and the brake valve. 

With the pressure controller the excess pressure is 
confined to the main reservoir and, while it has sufficient 
capacity to release the brakes promptly and recharge the 
auxiliary reservoirs on a train of any length, there is no 
danger of overcharging the auxiliary reservoirs on the 
forward end of the train. Thus, the possibility of a 
reapplication of the brakes on the forward end of the 
train is prevented during the charging of the rear brakes. 

Styles of Controllers. The controller is made in two 



B3 LOCOMOTIVE BRAKE EQUIPMENT. 285 




Fig. 121. 

styles, single and duplex, to cover the requirements of 
the different schedules. Fig. 121 is a sectional view of a 
duplex regulating part and Fig. 122 a similar view of a 
single regulating part. 

Figs. 123 and 124 show the three-way and the four- 
way cut-out cocks, which are used to control the air pres- 




Pig. 122. 



286 B3 LOCOMOTIVE BRAKE EQUIPMENT. 

sure to the regulating heads. Plate 15 is a sectional view 
of the supply portion of the controller. By referring to 
Plate 15 you will notice that Fig. 1 shows end view and 
Fig. 2 a cross sectional view. It will be noted that the 
connection with the main reservoir is made at MR, and 
by means of the cored passage, air is free to pass to the 
under side of valve PG 95. Connection BV leads to the 
brake valve and main reservoir connection, and connec- 
tion D to the regulating part (single or duplex), also 
connecting at D on Plate 15, Fig. 2. 

Operation. In operation, with either a single or a 
duplex regulating part, as soon as the pressure in the 
brake pipe is sufficient to overcome the resistance of 
spring PG 10, which holds diaphragm PG 13 seated over 




EVlSS^ 




Fig. 123. 



Fig. 124. 



port B, the pressure will pass through passage E to con- 
nection D and through piping to space E in the supply 
part of the controller above piston PG 4, forcing the 
piston and valve PG 95 down until seated and cutting 
off communication between the main reservoir and the 
brake pipe. 

As soon as the pressure in the brake pipe falls below 
the resistance of spring PG 10 the latter will force 
diaphragm PG 13 to its seat, closing off port B, where- 
upon the pressure in passage E and the piping connect- 
ing the supply and regulating parts, and space E above 
piston PG 4, will immediately escape to the atmosphere 



B3 LOCOMOTIVE BRAKE EQUIPMENT. 287 

through small port C in the regulating head of the con- 
troller, after which the main reservoir pressure will lift 
valve PG 95 off its seat and again open communication to 
the brake valve, thus maintaining a constant pressure in 
the brake pipe. 

Port X in the supply part of the controller connects 
the under side of piston PG 4 with the atmosphere, so 
that it will be free to operate and to discharge any leak- 
age past ring PG 24 or valve PG 95. 

Regulating Parts. The regulating parts are provided 
with brackets so that they can be attached to the cab in 
a position convenient for adjustment. The adjustment 
of these regulating heads is accomplished by means of 



lyJCopMr W»» 



ICttMrPto* 




Fig. 1. 



i{n»rha. 




Fig. 2. 
Plate 15, Figs. 1 and 2. 



nut PG 35, which regulates the tension of spring PG 10. 

As each regulating head has a vent port C to avoid 
waste of air with all duplex regulating parts, one of these 
heads should be plugged with a screw PG 33. 

Three- Way and Four-Way Cock Connections. By 
referring to the piping diagram it will readily be seen how 
the three-way cock is connected with the regulating 



288 B3 LOCOMOTIVE BRAKE EQUIPMENT. 

heads in schedule B3-HP and how the four-way cock 
is connected to the regulating heads and accelerator reser- 
voir in schedule B3-HS. 

Use of Cut-Out Cock. As before stated, the cut-out 
cock shown on Fig. 124 is used with the B3-S equip- 
ment between the regulating and the supply parts. When 
the cut-out cock is closed the supply part of the con- 
troller is cut off, making it inoperative, for the reasons 
given in the previous instructions. 

Cutting Out the Controller. The hand wheel PG 45 
can be used in case of any defect that causes a sluggish 
action of the controller. By screwing the wheel up it 
will lift valve PG 95 off its seat and allow the free pas- 
sage of air from the main reservoir to the brake valve. 
The controller will then be inoperative, and main reser- 
voir and brake pipe pressures will be equal until the 
controller is again put in working condition. 

Size of Controller to Straight Air Brake. A 24-inch 
controller is used to control the straight air brake pres- 
sure. It is located in a %-inch pipe, which is attached 
to the main reservoir pipe between cut-out cock No. 4 
and the i^-inch controller, and leads to the main reser- 
voir connection of pipe bracket EV 326. The regulating 
head is connected to the straight air pipe between the 
pipe bracket and the double check valve. It is adjusted 
to 40 pounds, and maintains that pressure in the locomo- 
tive brake cylinders when the straight air ' brake is 
applied. Its operation is identical with that of the i%- 
inch pressure controller. 

Double Check Valve. A double check valve is used 
with this type of equipment, and in all cases it is of the 
type used with the independent straight air equipment. 
It is so placed in the pipe connection that when the auto- 
matic brake is used the double check moves over and 
closes communication between the brake cylinder and 



B3 LOCOMOTIVE BRAKE EQUIPMENT. 289 

the straight air release, and when the straight air is used 
it moves over and closes communication from the brake 
cylinder to the triple exhaust. The piping diagram 
shows the location, and it works upon the same principle 
as the Westinghouse double check, which is illustrated 
and described on pages 139 and 140. 

DEFECTS OF THE PRESSURE CONTROLLER. 

If leather seat SA 6 leaks it will allow the main drum 
pressure to leak by the valve and overcharge the brake 
pipe. If the passage leading to piston PG 24 is stopped 
up, or the tension of spring PG 10 is too great, or if there 
is a leak by the diaphragm with the vent port in the 
spring casing stopped up, a leak by piston PG 24, a leak 
by the stem of valve PG 95 with port X stopped up, or 
piston PG 24 stuck in the bushing, the brake pipe will 
become overcharged. 

To overcome these defects temporarily, and until 
repairs are made, the low pressure pump governor of the 
duplex should be adjusted to shut off the pump at any 
desired pressure. 

If the pipe leading to the single controller, or the pipe 
leading from the brake valve to the cut-off cock breaks, 
the pump governor should be adjusted to regulate the 
required amount of pressure, and the pipe leading to the 
controller plugged. 

If any one of the pipes leading from the reversing cock 
to the controller top breaks, the reversing cock should be 
turned, and the other controller top cut in and adjusted 
to carry the proper pressure. 

If the controllers or pump governor require cleaning, 
and there is pressure in the main reservoir, the pump 
should be shut off and the reversing cock turned so as to 
shut off the pressure from the governor or controller that 
needs cleaning. The tension of the spring should then 



290 P>3 LOCOMOTIVE BRAKE EQUIPMENT. 

be slacked off, the air pipe disconnected and the spring 
box removed, after which the different parts may be 
cleaned and replaced. 



ACCELERATOR VALVE. 

It is well known that with the ordinary brake valves 
alone it is almost impossible, even with a full service 
application, to set all the brakes on a train of from 75 to 
100 cars. This is due to the back flow of air from the 
auxiliary reservoirs to the brake pipe through the feed 
grooves, and from the brake cylinder to the atmosphere 
through the leakage grooves. It is the result of the com- 
paratively slow brake pipe reduction through the service 
application ports of the brake valve, which for obvious 
reasons cannot be enlarged. 

List of Parts. The names of the parts are as follows : 

PG 24. Piston Ring. RV 70. Leather Seat. 

RV 62. Body. RV 74. Slide Valve. 

RV 63. Upper Cap. QT231. Spring. 

RV 64. Lower Cap. EV 656. Slide Valve Spring. 

RV 65. Piston. HS 24. >4-inch Street Ell. 

RV 67. Valve Stem. 

Purpose of the Accelerator. The purpose of the accel- 
erator valve is to overcome this difficulty. Its duty is to 
assist the brake valve in discharging brake pipe air when 
making service reductions with long trains, and to bring 
about a more uniform and prompt application of the 
brakes than is possible with the ordinary brake valves. 
It operates only when a service application is made, and 
then only when the volume of brake pipe air is sufficient 
to warrant its use. The reductions, however, are no 
greater with the accelerator valve than with the former 



B3 LOCOMOTIVE BRAKE EQUIPMENT. 291 

types of brake valve, as the automatic cut-off of the 
brake valve controls the flow of air that actuates the 
accelerator. This valve does exactly what its name 
implies ; it accelerates the discharge of brake pipe air. 
The operation of the accelerator valve is automatic ; it 
opens about 4 seconds after the brake valve handle has 
been moved to the graduating notch and closes in about 
the same length of time, after the graduating valve has 
closed ports F and S in the slide valve. A pressure of 
from about 10 to 12 pounds in the large compartment of 
the divided reservoir is required to operate it ; conse- 
quently it does not open with a shorter train than one of 
8 cars, as Avith a train of this length the automatic lap 
of the brake valve takes place before sufficient pressure 
has been accumulated in the divided reservoir to move 
the piston of the accelerator valve down against the 
spring. 

The accelerator valve is bolted to the divided reser- 
voir, the large chamber of which is the accelerator reser- 
voir and the small one the supplementary reservoir. 

Arrangement of Piping. The arrangement of the 
piping is shown in the piping diagrams. Plate 16, Fig. 2, 
is an outside view of the valve, showing the brake pipe 
connection and exhaust elbow, and Plate 16, Fig. 1, is a 
sectional view. 

Brake Pipe Pressure. Brake pipe pressure is always 
present in chamber O, around slide valve RV 74, and is 
prevented from escaping to chamber B by leather seat 
RV 70, which is held to its seat by spring QT 231. There 
is an oblong port a in the slide valve and a triangular port b 
in the slide valve bushing with its point upward. 

Operation. When the brake valve is placed in serv- 
ice position port S in the slide valve is open to the brake 
pipe, and the long port Ac, which is also in the slide valve, 
registers with port T in the seat, allowing brake pipe air to 



292 B 3 LOCOMOTIVE BRAKE EQUIPMENT. 



pass through ports S and T to the accelerator reservoir and 
to the top of piston RV 65, which is always in direct com- 
munication with the accelerator reservoir. When a pressure 
of from 10 to 12 pounds is accumulated in the reservoir the 
piston, valve stem and slide valve are moved down, com- 



PG 24 




R V 63 



HS 24 



g Brake Pipe' / 




R V 64 



Fig. 1. 



Plate 16. 



Fig. 2. 



pressing spring OT 231. Port a then registers with port b, 
but, as the small part of the port opens first, the brake pipe 
air flows slowly to the atmosphere, the discharge increasing 
as the port opens wider, until the full travel of the piston 
and slide valve gives a full opening of the port. When the 
cut-off valve of the brake valve goes to automatic lap and 
closes port S, air ceases to flow to the accelerator reservoir. 
The pressure on piston RV 65 reduces through ports R and 
T in the body of the valve and through port S in the piston. 
As soon as the pressure above the piston has been reduced 
sufficiently, spring QT 231 pushes the slide valve and piston 
upward, first closing port R, then ports a and b, lastly clos- 



B 3 LOCOMOTIVE BRAKE EQUIPMENT. 293 

irig leather seated valve RY 70 and stopping the flow of 
brake pipe air to the atmosphere. The piston closes port R 
before the slide valve closes port b, so that the air from the 
accelerator reservoir flowing more slowly through port S 
in the piston gives the slide valve the slow closure desired. 
The action of the accelerator valve allows a much larger 
volume of air to pass from the brake pipe than could flow 
in the same time through service ports F and G in the brake 
valve, and it will remain open longer with a long train than 
with a short one, as the volume of brake pipe air to be 
reduced is greater and cut-off valve EV 317 stays open 
longer. 

DEFECTS OF THE ACCELERATOR VALVE. 

If there is -a leak by slide valve RY 74, due to dirt, 
scale or the valve being cut, air will continue to flow from 
the valve, which will have the same effect as a leak from 
the brake pipe. If the leak affects the proper operation 
of the brakes, the valve should be cut out by turning the 
cut-out cock ; if not equipped with a cut-out cock, a blind 
gasket should be placed in the pipe leading to the accel- 
erator. The same action should be taken if spring QT 
231, or port S in piston RY 65, is stopped up ; if port S is 
stopped up, the pressure cannot escape and therefore 
holds the piston down. This will allow all brake pipe 
pressure to be exhausted. When this difficulty is encoun- 
tered the nut in the pipe leading to the divided reservoir 
should be slacked up. 

If, with a long train, the accelerator valve fails to 
open at all when a heavy reduction is made, it may be 
due to the passage in the slide valve leading to the divided 
reservoir being stopped up, a leak in the pipe connection, 
a leak by piston packing ring PG 24, which would allow 
the air to escape too fast without forcing piston RY 65 
down, or piston RY 65 becoming stuck in the bushing. 



294 B 3 LOCOMOTIVE BRAKE EQUIPMENT. 

If ports R and S are stopped up it will allow the pres- 
sure to equalize on both sides of piston RV 65, prevent- 
ing the piston from being forced downward. If leather 
seat RV 70 is worn and does not seat properly, allowing 
air to leak past it, with ports R and T stopped up, it will 
have the same effect. 

If ports R and T are open, and leather seat RV 70 
leaks, there will be a constant flow of air at these ports, 
which will have the same effect as a brake pipe leak, but 
will not prevent the valve from operating. 

QUICK RELEASE VALVE. 

The quick release valve, shown in Fig. 128, is for use 
with schedule B3-S switch engine equipment. This valve 
is for the purpose of hastening the release after an appli- 




RV( 144 
QTj 39 



EV254 
EV 255 

V253 



Fig. 128. 



cation of the automatic or straight air brakes. Connec- 
tion A leads to the double check valve, as shown in the 
piping diagram of this equipment ; connection B leads to 



B3 LOCOMOTIVE BRAKE EQUIPMENT. 295 

the driver brake cylinders, and connection X to the 
exhaust. 

As soon as the brakes are applied by automatic or 
independent application, pressure passes to the top of 
piston RV 142, forcing the latter down against the resist- 
ance of spring RV 138, until it strikes the collar on valve 
RV 141, clearing the valve body sufficiently to give a 
direct opening to the brake cylinders. 

In effecting a release, as soon as the handle of the 
brake valve has been returned to release position, the 
pressure will be reduced from the upper side of the 
piston, allowing the pressure on the under side to operate 
it and lift valve RV 141 off its seat, allowing the dis- 
charge of pressure from the brake cylinders to the atmos- 
phere. 

W nile the quick release valve is shown between ine 
double check and driver brake cylinders in the piping 
diagram it can, if desired, be placed in the straight air 
pipe between the brake valve and the double check, in 
order to hasten release of the straight air brakes on the 
engine and tender, leaving the release of the automatic 
brakes normal. 

List of Operative Parts. The operative parts are as fol- 
lows : 

RV136. Cap. RV140. Valve Seat. 

RV 138. Spring. RV141. Valve. 

RV 139. Valve Guide. RV 142. Piston. 

HIGH SPEED CONTROLLER. 

List of Operative Parts. The operative parts are as fol- 
lows : 

RV 103. Regulating Nut. RV 129. Lever Handle. 
RV 104. Cap Nut. RV 130. Lever Handle Pin 

RV 1 05 A. Regulating Spring. with Cotter. 



296 B 3 LOCOMOTIVE BRAKE EQUIPMENT. 



RV 131. 
RV 132. 
RV 133. 

HS 105. 



Valve Stem. 
Valve Seat. 
Valve. 
Cap. 



HS 107. Piston. 

HS 108. Piston Valve. 

SA 6. Leather Seat. 



The high speed controller is used with schedule 
B3-HS. Fig. 129 is a sectional view of this appliance 
showing the operative parts, which are as follows: HS 
107, Piston, with Valve ; HS 108, which is provided with 



D 

HS 108 

HSI06 




To Brake Cylinders 
W Pipe 



HSI05 
SIIO 
HSI09 
HS 107 

Fig. 129. 



To Brake Pipe 
Vz' Pipe 



BP 



one large and one small Annular Groove ; RV 105 A, 
Spring; RV 131, Valve Stem; RV 133, Pop Valve, and 
RV 129, Lever Handle. 



B3 LOCOMOTIVE BRAKE EQUIPMENT. 297 

The high speed controller is connected to the brake 
cylinders at BC and to the brake, pipe at BP. Its normal 
position is as shown in the illustration, where it is held 
by brake pipe pressure. During all ordinary service appli- 
cations the piston remains in this position, and the brake 
cylinder pressure can pass freely to the safety valve, 
through the large groove, when it is higher than the pres- 
sure that the safety valve is set to retain. Ports F and 
D allow the brake cylinder pressure to circulate around 
piston HS 107 and back of valve HS 108, which allows 
them to move with only a slight difference in pressure. 
However, when an emergency application is made, the 
brake pipe pressure is greatly reduced, and the brake 
cylinder pressure forces the piston and valve their full 
travel to seat C. This movement brings the smaller 
groove directly under passage G, which restricts the 
passage of brake cylinder air to the safety valve and 
causes a gradual reduction until stopped by the safety 
valve. The safety valves should be adjusted at 53 pounds, 
and whether used alone or with the high speed controller 
are piped to the engine brake cylinders, so that they will 
relieve the cylinders of all pressure in excess of 53 
pounds, whether obtained with the automatic or straight 
air application. 



LEVER SAFETY VALVE. 

Fig. 130 is a sectional view of the lever safety. valve, 
furnished with schedules B3, B3-S and B3-HP. The top 
portion of this valve is adjusted and operated in the same 
manner as that of the high speed controller lever safety 
valve and is adjusted at 53 pounds. 



298 B3 LOCOMOTIVE BRAKE EQUIPMENT. 

List of Operative Parts. The operative parts are as fol- 
lows : 

RV 103. Regulating Nut. RV 127. Valve. 

RV 105 A. Regulating Spring. RV 129. Lever Handle. 
RV 107. Valve Seat. 




Fig. 130. 

TERMINAL TESTS OF THE NEW YORK B3 

EQUIPMENT, AND HOW TO LOCATE 

AND REMEDY DEFECTS. 



As reported to the Traveling Engineers' Convention by the Com- 
mittee on Terminal Tests and the Locating of Defects, at Detroit, Aug- 
ust 25, 1908. 

B 3 ENGINE EQUIPMENT. 

The defects in this equipment have been very few, up 
to the present time, and are maintained at less expense 
than the older equipment. The corresponding parts are 
tested and maintained about the same as the former 
equipment. 



B 3 LOCOMOTIVE BRAKE EQUIPMENT. 299 



ENGINEER'S BRAKE VALVE. 

Before leaving the shop or going out on the road the 
engineer should know that the automatic lapping feature 
of the brake valve is in condition ; if not, the trouble may 
be found at the equalizing piston packing leather EV 
107, as shown in cut, or the supplementary reservoir and 
connections, due to leakage. The piston packing leather 
can be tested by closing the brake pipe cut-out cock 
under the brake valve, and placing the latch of the 
engineer's valve handle at a point one-half inch from 
the last service graduating notch toward the emergency 
position. If a blow continues for a short time after 
the brake pipe has been exhausted, the leather is leaking. 
The cut-out cock and slide valve should be tight in 
making this test. The other part can be tested with soap 
suds or torch. If the supplementary reservoir pipe should 
break, the automatic lapping feature of the valve would 
be lost, and a blind gasket or a plug should be used in 
the union connections or pipe and the brake pipe exhaust 
should be closed by the engineer moving the brake valve 
handle slowly to positive lap position. If the main slide 
valve is leaking, the same can be tested by pumping up 
full pressure, and placing the handle of the engineer's 
valve in lap position ; open the rear angle cock, exhaust- 
ing all air out of brake pipe and bleed auxiliary reservoir, 
immerse the hose coupling in a bucket of water and if 
bubbles arise, the slide valve is leaking. Another method 
of making this test is to pump up full pressure and place 
brake valve in lap position, open rear angle cock, exhaust- 
ing all air from brake pipe, then close cut-out cock below 
brake valve and if a continuous blow is found at brake 
pipe exhaust port, the slide valve is leaking. 



300 B3 LOCOMOTIVE BRAKE EQUIPMENT. 

B2 ENGINEER'S VALVE. 

This valve performs about the same functions as the 
B-3 engineer's valve, excepting that in full release posi- 
tion the air is taken from the brake pipe side of control 
valve instead of the main reservoir, for the straight air 
feature, as with the B-3 valve. 

When replacing the top cover on this valve care 
should be taken in having the gasket in condition, in 
order to avoid any leakage into the supplementary reser- 
voir through port O. The possible chance of leakage at 
this point has been avoided in the B-3 valve. 

The packing leather in the equalizing piston can be 
renewed in either the B-2 or B-3 valves, without remov- 
ing the piston by taking the front follower off. 

PRESSURE CONTROLLER. 

The pressure controller is in reality a part of the brake 
valve, taking place of the excess pressure or feed valves, 
and is connected in the main reservoir pipe near the 
brake valve to control brake pipe pressure. The principle 
of operation is the same as a pump governor. The regu- 
lating and supply portions are separate, being connected 
by piping^ and the regulating heads connect directly to 
the pipe between the supply port and the brake valve. 

In case it is necessary to equalize both main reservoir 
and brake pipe pressures, the same can be done by screw- 
ing up the control valve wheel PG 45 and unseating valve 
PG 166 

This valve should be located away from the heat as 
far as possible to preserve the leather seat of the valve. 

Should the brake pipe and main reservoir pressures 
equalize with the wheel PG 45 at the bottom or normal 
position, the leather seat is dirty or worn out, and should 
be cleaned or renewed. This trouble may also be caused 



B 3 LOCOMOTIVE BRAKE EQUIPMENT. . 301 

by improper adjustment of controller valve top or port B 
stopping up. 

If a blow exists at port X the piston packing ring or 
valve stem and bushing of valve PG 166 is leaking. A 
worn valve stem or bush will cause a constant blow at 
this port. 

There is a vent port in the regulating portion of the 
controller, which is located in one or the other of the 
small screws, which muffles the noise, when blowing, and 
should always be open, and when brake pipe has reached 
lis maximum pressure should blow. 

If air escapes from vent port before the required pres- 
sure is reached, there is dirt under diaphragm or same is 
distorted and should be repaired or renewed. 

ACCELERATOR VALVE. 

This valve does what its name would imply. It accel- 
erates the discharge of brake pipe air. The operation of 
the accelerator valve is automatic ; it opens about 4 sec- 
onds after the brake valve handle has been moved to the 
graduating notch, and closes in about the same length of 
time after the graduating valve has closed the service 
ports. It requires about 10 to 12 pounds pressure in the 
large compartment of the divided reservoir to operate it, 
consequently it does not open with a shorter train than 
eight cars as with that length of train the automatic lap 
of the valve takes place before sufficient pressure has 
been accumulated in the divided reservoir to move the 
piston of the accelerator valve down against the spring. 

In case the accelerator valve pipe should leak or 
break, the operation of the accelerator valve would be 
effected and should be repaired on arriving at the shop. 

Should the accelerator valve become defective for any 
reason, a blind gasket may be put in the brake pipe con- 
nection union until repairs can be made. 



302 B3 LOCOMOTIVE BRAKE EQUIPMENT. 

In case there is a continued blow at the exhaust port 
of the accelerator valve, the slide valve RV 74 is leaking 
or dirt on its seat, and should be cleaned or repaired. 

If a blow occurs at the accelerator valve exhaust, 
when making a second notch service application with a 
lone engine or a short train, the spring QT 231 is too 
weak or broken or port S is stopped up. 

If continuous blow exists at vent port T, leather seat 
RV 70 is leaking and should be renewed. 

HIGH SPEED CONTROLLER VALVE. 

With the B-2 or B-3 high speed equipment, which has 
the high speed controller connected to both brake pipe 
and brake cylinder, there is a possibility of the leather 
seat SA 6 getting dirty or worn, which would allow brake 
pipe air to feed into brake cylinder. To locate this 
trouble, the brake cylinder pipe can be disconnected at 
the union connection, and if the air escapes the leather 
seat is leaking. 

The leather seated valve SA 6 on the opposite side 
should be kept tight so as to avoid leakage from brake 
cylinder into the brake pipe, when brake pipe pressure is 
less than brake cylinder pressure. 



N. Y. QUICK ACTION TRIPLE VALVES. 303 



NEW YORK QUICK ACTION TRIPLE 

VALVES. 

List of Parts. The parts of the quick action triple valve 
shown in Figs. 131 to 136 inclusive, are as follows: 



QT 3. Packing Ring. 
QT 9. Exhaust Valve 
Spring. 

QT 20. Rubber Seating on 
Valve QT 71 

QT 28. Triple Strainer. 

QT ^2. Drainage Plug. 

QT 38. Exhaust Valve. 

QT 45. Packing Ring in 
Piston QT 129. 

QT 48. Graduating Valve. 

QT 49. Graduating Spring. 

QT 71. Vent Valve. 

QT 117. Non-Return Check. 

QT 128. Triple Piston, hav- 
ing an extension 
which forms a 
cylinder in which 
Vent Valve Pis- 
ton QT 129 op- 
erates. 



QT 126. Triple Head or Cap. 

QT 130. Middle Section of 
Flange and seal 
for Vent Valve, 

QT 132. Vent Valve Spring 

QT 133. Leather Gasket. 

QT 134. Rubber Gasket. 

QT 135. Cap Bolt. 

QT 136. Emergency Cap 
Bolt. 

QT 137. Quick Action Pis- 
ton. 

QT 138. Quick Action Valve 

QT 140. Quick Action Valve 
Spring. 

QT 141. Quick Action Valve 
Cap Nut. 

QT 142. Stop for Piston QT 
129. 



This triple valve is called a quick action triple for the 
reason that when an emergency application is made it 
carries auxiliary reservoir air to the brake cylinder almost 
instantly, equalizing the pressure through the large open- 
ing, past the quick action valve, augmented to some 
extent through the service opening past the graduating 
valve and, by reason of venting brake pipe air to the 



304 N. Y. QUICK ACTION TRIPLE VALVES. 

atmosphere, it produces a quick serial action of all other 
quick action triples throughout the train. 

When a service application is made air passes slowly 
from the auxiliary reservoir to the brake cylinder, 
through the graduating service port only, and there is no 
local venting of brake pipe air. 

The quick action triple valve, as shown respectively in 
release service, lap and emergency positions in Figs. 131, 
132, 133 and 134, is used on freight cars. Port F of this 
triple valve is drilled through the stem, the same as it is 
on the new passenger triple valve. 

Ports and Passages. Small port F drilled through 
piston stem QT 129 is to supply air from the brake pipe 
to chamber G, between pistons QT- 128 and QT 129; 
passage K in the body of the triple valve is for the pur- 
pose of allowing air from the auxiliary reservoir to pass 
to the emergency valve QT 138; L, L is a passage in the 
body of the triple valve between valves QT 138 and QT 
117, and is for the purpose of venting air from the 
auxiliary reservoir to the brake cylinder when the 
emergency brakes are used ; QT 125 is the lower portion 
of the triple valve body, known as the drainage and 
where the pipe connection is made at triple valve W ; H 
is a passage leading from vent valve QT 71 to quick 
action piston QT 137 and to the atmosphere at J. The 
feed groove in the triple valve body cylinder is at B. 

Course of Air. .Fig. 131 shows the course of the air 
(indicated by arrows) from the time it enters the triple 
valve until it enters the auxiliary reservoir. Air enters 
the strainer at W, passes through passage A into cham- 
ber E, past piston QT 128, through feed groove B and 
thence to the auxiliary reservoir at C, until the brake 
pipe and auxiliary reservoir pressures are equalized. 

Operative Parts. Fig. 132 shows the following prin- 
cipal operative parts of the New York quick action triple 



N. Y. QUICK ACTION TRIPLE VALVES. 305 



valve in service application; QT 128, Alain Triple Piston; 
QT 38, Exhaust Slide Valve ; OT 48, Graduating Slide 
Valve; OT 129. Vent Piston. 

Main piston OT 128 has the same movement for serv- 



QT 137 



QT 139 




Fig. 131. 



ice and emergency applications and is extended to form 
a cylinder in which vent piston QT 129 is fitted. A small 
port and passage F is drilled through the stem of piston 
QT 129 which allows brake pipe air to pass into chamber 



306 N. Y. QUICK ACTION TRIPLE VALVES. 

G, formed between the vent valve piston and the main 
triple piston, equalizing the pressures on both sides of the 
vent piston. 

Service Application. When a service reduction of 
brake pipe air is made, reducing the pressure in chamber 



QT 137 



QT 139 




Fig. 132. 



E, the auxiliary reservoir pressure being the greater 
forces piston QT 128 toward the weaker pressure, closing 
feed groove B. Port F is made of such size that when 



N. Y. QUICK ACTION TRIPLE VALVES. 307 

main piston QT 128 moves slowly to the left in a service 
application, as shown in Fig. 132, thereby reducing the 
size of chamber G, the air in chamber G will pass through 
port F to the brake pipe without moving piston QT 129 
from its normal position. In a service application the 
triple piston moves over only a portion of its stroke, 
bringing the small service port in the slide valve QT 48 
opposite the port in its seat leading to the brake cylinder, 
the quantity of air admitted being in proportion to the 
brake pipe reduction. If the brake pipe pressure is 
reduced but little, the pressure in the auxiliary is reduced 
by expansion into the brake cylinder to slightly less than 
that in the brake pipe. When piston QT 128 starts back 
and carries graduating valve QT 48 to lap position, as 
shown in Fig. 133, it closes the service port without dis- 
turbing exhaust valve QT 38, thus closing communica- 
tion between the auxiliary reservoir and the brake cylin- 
der. 

The plain triple valve has the triple piston, the 
exhaust valve and the graduating valve. The additional 
valves described in the list of parts are for use in emer- 
gency applications for the purpose of allowing the triple 
valve to vent the brake pipe air to the atmosphere and at 
the same time cause quick equalization of the auxiliary 
reservoir and brake cylinder pressures. 

The additional parts of the quick action triple valve 
brought into use when an emergency application is made 
are, Vent Valve Piston QT 129, Vent Valve QT 131, 
Quick Action Piston QT 137 and Quick Action Valve 

QT 138. 

In service applications these parts remain inoperative, 
but in an emergency application they are carried into 
action. Vent valve QT 131 is held to its seat by spring 
QT 132, assisted by brake pipe pressure, and is opened 
by piston QT 129. When the piston is forced to the 



308 N. Y. QUICK ACTION TRIPLE VALVES. 

left, quick action valve QT 138 is held to its seat by 
spring QT 140, assisted by auxiliary reservoir pressure, 
and it can only be opened when quick action piston QT 
137 moves to the right. 




Fig, 133. 



Emergency Application. In an emergency application 
a quick reduction is made in the brake pipe pressure, and 
main piston QT 128 moves quickly to the left. The air 
from chamber G cannot flow through port F fast enough 



N. Y. QUICK ACTION TRIPLE VALVES. 309 



to reduce the pressure at the same rate as it is being 
reduced in the brake pipe, and a momentary excess pres- 
sure takes place in chamber G, sufficient to force piston 
QT 129 to the left, which in turn forces vent valve QT 



QT 137 



-QT 139 

-QT 138 




QT 119 



Fig. 134. 



131 from its seat. The vent valve being off its seat, brake 
pipe air enters passage H and escapes to the atmosphere 
through port J, but before the air escapes through port 
J it exerts a strong pressure upon quick action piston QT 



310 N. Y. QUICK ACTION TRIPLE VALVES. 

137, forcing it to the right and causing it to unseat quick 
action valve QT 138. This allows the auxiliary reservoir 
air to flow rapidly through the large passage K, past the 
non-return check valve QT 117 and to flow through pas- 
sage L, to the brake cylinder, shown in Fig. 134. 

Releasing. The brakes are released by restoring the 
brake pipe pressure until it exceeds that in the auxiliary 
reservoir, causing main piston QT 128, exhaust valve 
QT 38, and graduating valve QT 48 to return to their 
normal positions (Fig. 131), closing the service port, 
allowing the auxiliary reservoir to charge through feed 
groove B, and at the same time allowing the air in the 
brake cylinder to escape to the atmosphere through the 
exhaust cavity of exhaust valve QT 38 and the exhaust 
port in its seat. 

Brake Cylinder Pressure. In a service application 
the quick action triple valve allows the auxiliary reser- 
voir pressure to pass to the brake cylinder gradually, as 
required to produce the necessary braking force, while in 
an emergency application it allows the full auxiliary 
reservoir pressure to pass almost instantly into the brake 
cylinder, applying the brakes with full force, and at the 
same time it vents sufficient brake pipe air to the atmos- 
phere to produce a quick reduction in brake pipe pres- 
sure, which causes the following quick action triple valve 
to operate in quick action, and so on throughout the 
train, producing a quick serial action of all the brakes. 

No greater pressure is produced in the brake cylinder 
in an emergency than in a service application, as the 
triple valve uses auxiliary reservoir air in both applica- 
tions. 

Partial Service Application. After a partial service 
application, an emergency application can be made, but 
the quick action parts will not operate in a manner so as 
to produce a quick operation of all the brakes and an 



N. Y. QUICK ACTION TRIPLE VALVES. 311 

instantaneous equalization of pressure in the brake cylin- 
der. However, if an emergency arises after a service 
application has been made, and the brake valve is placed 
in emergency position, allowing the brake pipe pressure 
to escape freely to the atmosphere, all the brakes on the 
train w T ill apply with their full braking power much more 
quickly than if a service reduction were made. The 
operation of the quick action triple can be obtained only 
when the pistons are separated with chamber G at its 
normal size. 

Auxiliary Pressure. As auxiliary reservoir pressure 
alone goes to the brake cylinder in both service and 
emergency applications, it might be considered that both 
applications will be equally effective. This is not the 
case, however, for the service application is slower than 
the emergency, and for this reason a full emergency 
application is much more effective than a full service 
application. When a partial reduction is made, followed 
by an emergency reduction, the comparative effective- 
ness depends on how heavy the service application is 
before the emergency application is made, and also upon 
the length of the train. However, when a service appli- 
cation is begun, and is then followed by an emergency 
application, the effectiveness of the brakes w T ill not be 
as great as if an emergency reduction had been made 
at first. 

Cars Cut Out. Two or three cars with brakes cut 
out placed together in a train will not prevent the quick 
action triple valves on the following cars from operating 
quick action. The number of cut-out triple valves that 
can be placed together in a train without interference of 
this kind depends largely on their location in the train, 
varying from three, placed together behind the first 
quick action triple valve, to six or eight, placed close to 
the rear of a 50-car train. 



312 N. Y. QUICK ACTION TRIPLE VALVES. 

Vent Valve. Vent valve QT 131 will not remain 
open and exhaust all the brake pipe air to the atmosphere 
when an emergency application is made. Port F is 
always open, and the moment chamber G excess pressure 
is exerted on piston QT 129 it quickly equalizes with 
brake pipe pressure, and spring QT 132, together with 
brake pipe pressure, w T ill return valve QT 131 to its seat, 
thus stopping the escape of air when the brake pipe 
pressure is reduced sufficiently to apply the brakes with 
full force. As valve QT 131 closes, piston QT 129 
returns to its normal position, its travel in that direction 
being limited by stop QT 142. Valve QT 138 and piston 
QT 137 will return" to their normal positions after 
equalization has taken place in the brake cylinder. 

PASSENGER QUICK ACTION STYLE "S" 
TRIPLE VALVE. 

List of Parts. The names of the parts of this new style 
of valve as shown on Figs. 135 and 136 are as follows: 

QT 9. Exhaust Valve QT 1 19. Non-Return Check 
Spring. Cap. 

QT 20. Rubber Seat on QT 126. Triple Head or 
Valve QT 71. Cap. 

QT 28. Strainer. QT 130. Middle Section of 

QT 32. Drainage Cap Plug. Flange and Seat 

QT 45. Packing Ring on for Vent Valve 

Piston QT 164S. QT 131. 

QT 49. Graduating Valve QT 132. Vent Valve Spring. 

Spring. QT 133. Leather Gasket. 

QT 71. Vent Valve. QT 134. Rubber Gasket. 

QT 117. Non-Return Check. QT 135. Cap Bolt. 

QT118. Non-Return Check QT 137. Quick Action Pis- 
Valve Spring. ton. 



N. Y. QUICK ACTION TRIPLE VALVES. 313 



QT 138. Quick Action Valve. 
QT 140. Quick Action Valve 

Spring. 
QT 141. Quick Action Valve 

Cap. 
QT 142. Stop for Piston QT 
•166S. 



QT 162S. Exhaust Valve. 

QT 163. Graduating Valve. 

QT 166S. Triple Piston (in- 
cluding Packing 
RingQT 3 ). 



Small port E is drilled through the piston stem for the 
purpose of supplying air from the brake pipe to chamber 






QT 135 
QT 131 
QT20- 
QT 71- 

/ ?/////////.-; : $Z 



QT 132Jf 
QT 125^ 
QT 143 
QT 142 




To Train Pipe 
V'Pipe 

QT28 
QT30' 
QT31 
QT29 



Fig. 135. 

G between QT 166S and QT 164S ; passage K in the triple 
valve body is for the purpose of allowing air from the 
auxiliary reservoir to pass to emergency valve QT 138; 
L, L is a passage in the body of the triple valve between 



314 N. Y. QUICK ACTION TRIPLE VALVES. 

valves QT 138 and QT 117; QT 125 is the lower portion 
of the triple valve body known as the drainage, and 
provides for the brake pipe connection at W. 

Graduating Valve and Ports. This style of valve 
used on 12, 14 and 16-inch brake cylinders is larger than 
the ordinary quick action triple valve ; it has a large 




QT 141 
QT 140 
QT 139 



Fig. 136. 



graduating port for the air to pass through to the brake 
cylinder; it also has a larger exhaust port and exhaust 
valve QT 162S, and has the graduating valve QT 163 
mounted on top of exhaust valve QT 162S (Fig. 135). 
Friction. The friction of the operative parts is 



N. Y. QUICK ACTION TRIPLE VALVES. 315 

reduced by placing graduating valve QT 163 on top of 
exhaust valve QT 162S. When triple piston QT 166S 
begins to move, the graduating valve moves first to uncover 
the service ports in exhaust valve QT 162S ; then the 
exhaust valve is moved until the graduating ports in the 
exhaust and its seat come in register. In this style of triple 
valve but one slide valve is moved at a time. 

Different Types. This style of triple valve can easily 
be distinguished from the freight and 10-inch passenger 
triple valves, as the letter "S" is cast in the body of the 
valve and the triple valve is fastened to the brake cylinder 
with three studs. The letter "S" is also stamped or cast 
on all parts of this valve that are not interchangeable with 
those of the other valves mentioned. 

The difference between styles "S" and "P" of the triple 
valve and the freight triple valve is that the side cap of the 
"S" and "P" is tapped out for a one-half-inch pipe, and 
a plug inserted. This is done for the purpose of attaching 
a pipe from the triple valve to the compensating valve with 
the high speed brake. 

DEFECTS OF THE NEW YORK QUICK ACTION 
TRIPLE VALVES. 

If graduating valve QT 163 in the style "S" triple valve 
leaks it can be detected by making a partial service reduc- 
tion, and then noting whether the brake released of its 
own accord. A leak of this kind will not allow the auxiliary 
pressure to escape through the exhaust port while exhaust 
valve QT 162S is in release position, for in this position it 
closes the opening from the auxiliary reservoir to the brake 
cylinder and atmosphere, and air leaking by the graduating 
valve QT 163 cannot escape. 

Cap Nut. If cap nut QT 141 is not securely fastened 
or the emergency valve leaks it will allow auxiliary reser- 
voir pressure to leak away the same as a slightly open 



316 N. Y. QUICK ACTION TRIPLE VALVES. 

release valve. If the amount of leakage is large it will 
cause the brake to release. 

Leaky Check Valve. If the check valve leaks or cap 
nut QT 1 19 is not securely tightened it will allow all brake 
cylinder air to leak away, reducing the braking power, the 
same as with a leaky piston packing leather. 

Blow at Port J . A constant blow of air from port J in 
the side of the triple valve indicates that the vent valve 
is leaking. If accompanied by a blow at the triple exhaust 
port it indicates that the quick action or emergency valve 
is leaking. If the vent valve leaks it will be indicated by 
the application of the brake when the cut-out cock in the 
cross-over pipe is closed ; but if the emergency valve leaks 
the brake will not apply with the closing of the cut-out 
cock. 

Maintaining Pressure. If it is difficult to maintain 
normal brake pipe pressure and the brakes will not release 
properly it indicates a bad leak in the brake pipe. The 
hose and brake pipe connections should be carefully exam- 
ined and it should be noted whether there is a blow at 
port J of the triple valve. The leakage will be coming 
direct from the brake pipe, due to vent valve QT 131 not 
being seated properly, or the rubber seat being defective. 

Brake Applying in Quick Action. If a brake applies 
in quick action when a service reduction is made it may 
be due to the packing rings in vent piston QT 129 fitting 
the cylinder too tightly, a weak vent valve spring QT 132, 
or small port F in vent valve piston QT 129 being 
stopped up. 

If the brakes do not apply in quick action when the 
proper reduction is made the packing ring of vent valve 
piston QT 129 may be worn or fit poorly. 

Blows at the Triple Exhaust. A blow at the triple 
exhaust would be due to leaky exhaust valve QT 38, leaky 
graduating valve QT 48, a defective gasket between the 



N. Y. QUICK ACTION TRIPLE VALVES. 317 

body of the triple valve and the brake cylinder head with 
passenger equipment, a defective gasket between the 
auxiliary reservoir and the triple valve with freight equip- 
ment, or a leak in the auxiliary tube leading from the 
triple valve to the brake cylinder. 

A leaky exhaust valve would cause a blow at the 
exhaust port, whether the brake were applied or released, 
and when applied it would cause the brake to release. 

Leaky Graduating Valve. A leaky graduating valve, 
with the triple valve in lap position, will allow the auxiliary 
pressure to escape under the graduating valve and through 
the port into the brake cylinder, reducing the auxiliary 
pressure and setting the brake with greater force. 
Whether this will allow the brake to release will depend 
upon whether or not the piston packing ring is tight. If 
the packing ring is in good condition the auxiliary reservoir 
pressure will continue to feed by the defective graduating 
valve until sufficient reduction exists between the brake 
pipe and the auxiliary reservoir to start the exhaust valve, 
when it may move to release position and release the brake. 

Defective Piston Packing Ring. If the piston packing 
ring or the piston is defective, the air leaks into the 
auxiliary reservoir as fast as it leaks by the graduating 
valve into the brake cylinder, the brake will continue to set 
instead of releasing, until the pressures are equal ; there- 
fore, under such conditions, a leaky graduating valve 
cannot release the brake. 

Failures of Brakes to Apply. A failure of the brakes 
to apply on a car when a brake pipe reduction has been 
made may be due to the feed grooves or strainer being 
stopped up, preventing the auxiliary reservoir from charg- 
ing, or the triple valve may be sticky, gummed or dirty, 
so that the piston cannot move. In this case the brake will 
not apply on the car with the defective triple when a 
service reduction is made. If a heavy reduction is made 



318 N. Y. QUICK ACTION TRIPLE VALVES. 

the triple valve may be forced loose and it will probably 
work satisfactorily during the remainder of the trip. 

Sticky Triple Valve. A sticky triple valve is sometimes 
the cause of a brake applying in quick action on a car 
during a service brake pipe reduction. In this case the 
triple valve will not usually respond to the first and some- 
times the second service reduction, and the brake on the 
car with the defective triple valve will not apply until 
the difference between the auxiliary reservoir and brake 
pipe pressure is sufficient to cause the triple piston to 
start from its stuck position and move forward quickly 
to emergency position, the stem striking sufficiently hard to 
compress spring QT 132 and open vent valve QT 131, thus 
causing quick application of the brakes on this car. 

Brakes Failing to Release. If a brake fails to release 
and there is a strong blow at port J it may be due to vent 
valve QT 131 being held from its seat by dirt or scale, or 
a badly worn triple piston packing ring, which would allow 
the brake pipe pressure to feed slowly by the packing ring, 
charging the auxiliary reservoir, without forcing the piston 
to release position, and releasing the brake. 

Hozv to Locate Defective Triple. To locate a leaky or 
defective triple valve, with a full brake pipe pressure, a 
reduction of from 5 to 10 pounds should be made, the 
amount depending on the length of the train. The brake 
piston that has failed to move out should then be looked 
for, and when it is found the brake on this car should be 
cut out and the test repeated in order to render it certain 
that the faulty triple valve has been located. On freight 
trains a sectional test should be made until the defective 
triple is located, as previously described. 



HIGH SPEED COMPENSATING VALVE. 319 

STYLE "A" NEW YORK HIGH SPEED 
BRAKE COMPENSATING VALVE. 

The high speed reducing valve, shown in Fig. 137, is 
called a compensating valve, for the reason that while 
operating in a service application, as an ordinary safety 
or pressure reducing valve, in an emergency application 




320 HIGH SPEED COMPENSATING VALVE. 

it holds the maximum cylinder pressure for a limited 
cime before commencing to relieve it. The period during 
which the pressure is held is automatically shortened or 
lengthened according to the variation obtained in the 
maximum brake cylinder pressure on the piston, or in 
both combined, as the valve makes allowance in the time 
of holding this pressure. On account o^ these variations 
the closure of all valves upon the tram will be practically 
uniform. 

List of Parts. The compensating valve consists of 
the following parts : HS JJ, Piston Valve, which works 
in a bushing or cylinder; HS 81, Packing Rings, there 
being two of these, either of which may act as a valve 
for the relief and leakage port ; HS n, Regulating Spring, 
by which the piston is held in its normal position against 
the brake cylinder pressure; HS 12, Regulating Nut or 
Screw, by means of which the tension of the spring is 
regulated ; HS 87, Non-Return Check Spring ; HS 76, 
Spring Box; HS 10, Cap Nut; HS 83, Non-Return Check 
Valve with casing complete. 

Emergency. In an emergency application the air 
vented from the brake pipe into spring box HS j6 passes 
non-return check valve HS 83, which then seats and 
prevents the air that is entrapped in the spring box from 
escaping, except as it passes out slowly through the 
small port drilled through the check valve (see piping 
diagram, Fig. 138). 

Piping. The compensating valve is connected with 
the brake cylinder and the triple valve as shown in the 
piping diagram (Fig. 138). With the style "A" compen- 
sating valve a one-half-inch pipe connection is made from 
the chamber above piston HS jy and the brake cylinder, 
and another pipe connection leads from the side cap of 
the quick action triple valve to spring box HS 76, which 



HIGH SPEED COMPENSATING VALVE. 321 

has direct communication with the air chamber below 
piston HS yy. All the pipe connections should be tight. 
Operation. When style "A" compensating valve is 
piped, as shown in Fig. 138, and an emergency appli- 
cation is made, a portion of the brake pipe air is vented 
at the side cap of the quick action triple valve and passes 
through the pipe leading to the non-return check valve 
and spring box chamber, charging the spring box 
chamber under the piston with air pressure. This 
pressure re-enforces the regulating spring pressure under 
the piston and permits the full equalization from the 
auxiliary reservoir to be had and retained for several 
seconds before piston HS JJ can descend and open the 

J/j PIPE TO 
BRAKE CYLINDER 




NON RETURN^ 2 ? 
CHECK VALVEly 

y 2 PIPE TO 
SIDE CAP OF TRIPLE 



Fig. 138. 



relief ports. The air vented into and entrapped in the 
spring box chamber requires several seconds to pass to 
the atmosphere through the small port in non-return 
check valve HS 83. When the air pressure in the spring 
box air chamber has been reduced sufficiently below 
brake cylinder pressure, the piston will be forced down- 
ward, the relief ports controlled by packing rings HS 81 
will be opened and the brake cylinder pressure will be 
gradually reduced to the point of adjustment of the valve. 
In a service application no air is vented into the 
spring box air chamber, and the only pressure which 



322 HIGH SPEED COMPENSATING VALVE. 

the piston has to overcome is that of regulating spring 
HS'n. Consequently when the pressure in the brake 
cylinder is sufficient to overcome the tension of the 
regulating spring the piston will be forced downward, 
promptly opening the relief ports. 

Attaching Spring Box. Care should be exercised 
when bolting the spring box to the body of the valve to 
see that gasket HS 90 is in good condition and that the 
bolts are drawn up tightly in order to form a perfectly 
air tight joint between the valve body and the spring- 
box, so that the air entrapped in the spring box chamber 
by the non-return check valve HS 83 will have no other 
means of escape than through the small port in the check 
valve, thus regulating the escape of the air. 

Packing Rings. The purpose of piston packing ring 
HS 81 is to form an air tight joint in the cylinder, pre- 
venting brake cylinder pressure from leaking past the 
piston into the spring box chamber, and it also closes the 
relief port when in normal position. 

The lower ports controlled by the lower packing rings 
are leakage ports and their function is to carry to the 
atmosphere whatever pressure may leak by upper 
packing ring HS 81, thus preventing any leakage into 
the spring box chamber that would tend to balance the 
piston and retard the escape of air from the brake 
cylinder. 

When piston HS 77 is in normal position, lower 
packing ring HS 81 covers the leakage ports and prevents 
the spring box air from leaking by this ring to the atmos- 
phere in emergency application. When piston HS 77 has 
moved to the lower end of its stroke, and the leakage 
ports to the upper and lower packing rings are about 
midway between the two rings, it is evident that any 
leakage by the upper packing ring will pass out through 
these ports. 



HIGH SPEED COMPENSATING VALVE. 323 

Advantages of High Pressure. The advantage of 
holding the maximum cylinder pressure obtained from a 
pressure of no pounds is that an emergency application 
is more effective in retarding the motion of the train at 
high speeds. If the maximum cylinder pressure is 
retained until the speed of the train has been reduced, the 
reducing valve will vent all surplus air above that 
pressure for which the adjusting spring is set, thus pre- 
venting the wheels from sliding at slow speeds. 

Also in service application two or more powerful 
applications can be made without recharging the 
auxiliary reservoirs, and there will still remain sufficient 
pressure to make an ordinary emergency application, 
such as would be had from a 70-pound brake pipe 
pressure. 

Use of Compensating Valve on Different Sizes of 
Cylinders. The compensating valve can be used on any 
size of cylinder. — 6, 8, 10, 12, 14 and 16-inch. The rate 
of reduction in brake cylinder pressure will be about the 
same with the 16-inch cylinder as with the 10-inch when 
the compensating valve is used. 

When the compensating valve is used on 10-inch and 
12-inch brake cylinders, union stud HS 14A is used. The 
opening through this stud is reduced or, in other words, 
there is a choke placed in it, which to a large degree 
regulates the flow of air from the brake cylinder to the 
compensating valve and through the latter to the atmos- 
phere. One size of this union stud goes with the 6 and 
8-inch, another with the 10 and 12-inch and another with 
the 14 and 16-inch brake cylinders. Therefore it will be 
seen that a size of choke can be used with each size of 
brake cylinder that will give exactly the same rate of 
reduction. The stud is the part that must be used with 
the corresponding size of brake cylinder, as but one style 



324 HIGH SPEED COMPENSATING VALVE. 

of compensating valve is used on the different sizes of 
cylinders. 

Adjustment. The compensating valve is usually 
adjusted to withstand a pressure of 60 pounds, although 
for driver brakes, tender brakes and such cars as are 
provided with a standard foundation brake gear the 
adjustment is sometimes varied from this. 



NEW YORK TRAIN AIR SIGNAL SYSTEM. 325 



NEW YORK TRAIN AIR SIGNAL 
SYSTEM. 

SIGNAL REDUCING VALVE. 

Fig. 139 is a cross sectional view of the signal reducing 
valve. X is the main drum connection and Y is the con- 
nection to the signal line. 

List of Operative Parts. The operative parts are as 
follows : 



SR 24. Supply Valve. 

SR 26. Supply Valve Spring. 

SR 27. Supply Valve Seat. 

SR 28. Piston Packing Ring. 

SR 29. Piston. 

SA31. Diaphragm Ring. 



SA 32. Diaphragm. 
SA 34. Regulating Nut. 
SR 41. Cut-Out Plug. 
SR 42. Choke. 
PG 141. Regulating Spring. 




PS 141 
SA34 



Fig. 139. 



326 NEW YORK TRAIN AIR SIGNAL SYSTEM. 

Operation of the Reducing Valve. The main drum 
pressure enters at X, and regulating spring PG 141, acting 
on diaphragm plate SA 32, causes the stem of the plate to 
hold supply valve SR 24 from its seat, so that the main 
reservoir pressure is free to pass through the supply valve 
to chamber B on top of the diaphragm and through 
passage C to the signal line at y, increasing the pressure 
in the signal line and chamber B until it reaches 40 pounds. 
When piston SR 29 is forced downward against the ten- 
sion of regulating spring PG 141, supply valve SR 24 is 
forced to its seat by main drum pressure and supply valve 
spring SR 26. When a reduction is made in the signal line 
the top of diaphragm SA 32 is affected. Regulating spring 
PG 141, forcing up on the diaphragm, unseats supply valve 
SR 24, compressing supply valve spring SR 36 ; the main 
drum pressure is then free to flow by the supply valve to 
the signal line, charging the latter in the manner described. 

SIGNAL VALVE. 

The signal valve, as shown in Fig. 140, is generally 
located under the footboard of the cab. The signal pipe 
is connected to it at X, while a pipe leads from Y to the 
signal whistle. The valve body is divided into two cham- 
bers, A and B, by a rubber diaphragm SV 3, which 
operates diaphragm stem SV 4A. This rubber diaphragm 
has two disks, the lower one SV 6 of brass and the upper 
one SV 12 of sheet iron, and through these disks is screwed 
a brass plug, through which a hole is drilled for the passage 
of air. Valve SV 8 is held to its seat by gravity and con- 
trols the passages leading to the whistle. There are three 
uprights AA that press against the disk or valve and lift 
it from its seat whenever diaphragm SV 3 rises. The 
clearance between the uprights and the disk of stem SV 8 
should not exceed i/iooth of an inch. 

Operation. When the signal pipe is being charged, 



NEW YORK TRAIN AIR SIGNAL SYSTEM. 327 

air enters the signal valve at X and, passing through 
small port J, charges chamber A. It also passes through 
passage CC and feeds down slowly to chamber B, 
charging it to the same pressure as chamber A. The 
pressures in chambers A and B and the signal pipe are 
equal when the signal line is fully charged. When the 
signal cord is pulled and a reduction is made in the 
signal line pressure it also causes a reduction of pressure 
in chamber A of the signal valve, but passage CC being 
very small the pressure in chamber A above diaphragm 
SV 3 reduces faster than the pressure in chamber B ; 




Fig. 140. 



consequently the diaphragm and uprights AA are forced 
upward and raise exhaust valve SV 8 from its seat, thus 
permitting the air in chamber A to flow into passage E 
leading to the whistle, which causes a blast. The same 
reduction of pressure that operates the signal valve also 
opens the reducing valve, which then allows the pressure 
from the main reservoir to pass through the reducing 
valve and into the signal line, raising the pressure to 
normal. This increase of pressure, following imme- 
diately after the reduction in the signal line, increases 
the pressure in chamber A faster than in chamber B, 
thus forcing the diaphragm downward and permitting 



328 NEW YORK TRAIN AIR SIGNAL SYSTEM. 

exhaust valve SV 8 to close passage E, thus stopping 
the flow of air to the whistle. 

All other parts of the New York air signal equipment 
not mentioned herein are interchangeable with and 
operate upon the same principle as those of the -Westing- 
house Air Signal equipment, previously described on 
pages 105 to 112. 

DEFECTS OF THE NEW YORK AIR SIGNAL 

SYSTEM. 

Although there are comparatively few parts in the 
air signal system it requires good judgment to locate 
defects that will cause improper operation. 

If the signal system fails to charge it should first be 
noted that the cocks between the first car and the tender 
are open ; if open, the lining of the hose may be loose, 
blocking the passage, and if in cold weather the signal 
line on the engine and tender may be frozen up or not 
cut in, or the regulating spring of the reducing valve 
may be broken. 

If the signal line charges but fails to respond when a 
reduction is made, it may be due to the clogging up of 
the strainer in the tee pipe connection of the branch 
pipe with the signal pipe. If this is the case the exhaust 
may sound all right, as there will be considerable air 
in the branch pipe between the strainer and the dis- 
charge, but the air in the main pipe will be unable to get 
past the strainer fast enough to make the reduction 
sufficiently quick to operate the signal valve ; or it may 
be that the small port of the signal valve is stopped up, 
preventing the air from entering the chamber above the 
diaphragm and charging the valve ; or the small port in 
the stem of the diaphragm may be stopped up, which 
will allow the chamber below the diaphragm to charge, 
but when a reduction is made in the signal line there 



NEW YORK TRAIN AIR SIGNAL SYSTEM. 329 

would be no pressure under the diaphragm to raise it, 
and no blast of the whistle would result. 

A failure of the whistle to sound may be due to 
improper adjustment of the bell of the whistle, the bowl 
becoming filled with dirt or by the whistle being placed 
in such a position that a draft from an open window may 
prevent it from sounding. 

If the whistle gives one long blast it may be due to 
the reductions being made too close together or by the 
disk becoming loose from its seat. 

If the whistle blows when the brakes are released it 
indicates that there is a direct communication between 
the main reservoir and the signal line, allowing the latter 
to become charged to main reservoir pressure. In releas- 
ing the brakes the pressure in the main reservoir is 
reduced, and if the opening is large enough and the 
main reservoir pressure is reduced sufficiently fast, air 
will flow from the signal line to the main reservoir, and 
the reduction in the signal line will allow the signal 
valve to operate, causing the whistle to give a blast. This 
may be caused by the regulating spring of the reducing 
valve being too great, a leak by the diaphragm with the 
vent port in the spring box stopped up, or the supply 
valve of the reducing valve being held from its seat by 
dirt or other foreign matter. 



SUMMARY OF AIR BRAKE OPER- 
ATION AND TRAIN HANDLING. 

DEFINITION OF THE AIR BRAKE. 

An air brake is a power brake operated by com- 
pressed air. 

TRACING AIR THROUGH THE BRAKE SYSTEM. 

The course of the air through the brake system is 
as follows: Air enters the strainer of the 9^-inch, 
n-inch and cross-compound pumps, and at the air inlets 
of the 8-inch pump, passes the receiving valve to the air 
chamber of the pump, is compressed by the air piston, 
passes the discharge valves to the discharge pipe, thence 
to the main reservoir, from the main reservoir through 
a return pipe to the engineer's brake valve, passes into 
the engineer's brake valve when it is in full release or 
running position, and through suitable ports to chamber 
D, from chamber D to the black hand of the air gauge ; 
also to the brake pipe and the pump governor of the D-8 
brake valve, through the cut-out cock below the brake 
valve, through the hose and couplings to the first closed 
angle cock in the train, and to the conductor's valve of 
each coach and way car, through the cross-over pipe and 
cut-out cock to the triple valve, and through the feed 
grooves of the triple valve, when in release position, to 
the auxiliary reservoir, charging the latter. When a 
sufficient reduction is made at the brake valve, or from 
the train line, it will cause the auxiliary reservoir pres- 

330 



AIR BRAKE OPERATION. 331 

sure to force the triple valve to set position, allowing 
auxiliary pressure to feed to the brake cylinder, thus 
applying the brake. Restoring the brake pipe pressure 
above that in the auxiliary reservoir, or reducing the 
auxiliary pressure below that in the brake pipe, will cause 
the triple valve to move to release position, allowing the 
air in the brake cylinder to pass to the atmosphere 
through the triple exhaust and retainer. Air from the 
main reservoir passes to the pump governor of the G-6 
and ET brake valves, to the red hand of the air gauge, 
to the. face of all valves on the engine operated by main 
reservoir pressure, and to the main reservoir side of the 
signal reducing valve. If the engine is equipped with 
straight air brakes it passes to the main reservoir side 
of the straight air reducing valve. 

BRAKE PIPE PRESSURE. 

A brake pipe pressure of 70 pounds should be car- 
ried with the ordinary brake, 90 pounds with schedule 
"U" equipment and no pounds with the high speed 
brake. 

The brake pipe pressure is regulated through the 
brake valve by means of the pump governor with the 
D-8 brake valve, through the feed valve attachment with 
the G-6 and ET equipments and with the pressure con- 
trol or pump governor with the Xew York brake 
equipment. 

EXCESS PRESSURE. 

Excess pressure is the amount of pressure carried in 
the main reservoir over and above that in the brake pipe. 
It should be carried at all times, except when charging 
a train at terminals or recharging while descending heavy 
grades, and it should be carried then if practicable. 

The amount of excess pressure that should be carried 



332 AIR BRAKE OPERATION. 

with the different styles of brake valves is as follows: 
With the D-8 brake valve, 15 pounds for short passenger 
trains and 20 pounds for freight or long passenger trains ; 
with the G-6 brake valve, single governor, 20 pounds for 
passenger or short trains and 30 pounds for long freight 
trains ; with the double governor, 20 pounds for pas- 
senger and short trains, with brake valve in either run- 
ning or lap position, and for long freight trains, 20 pounds 
in running position and 50 pounds in lap position ; with 
the schedule "U" or ET valve, 10 to 20 pounds in both 
running and lap positions, and the same with the New 
York brake. 

Purposes of Excess Pressures. Excess pressure is 
carried to insure a prompt and certain release of all 
brakes, especially with long trains, to insure a quick 
recharge of the brake pipe and auxiliary reservoirs, and 
to operate the different appliances on the locomotive that 
are operated by main reservoir pressure without inter- 
fering with the brake pipe pressure. 

A greater excess pressure is carried on freight than on 
passenger trains, for the reason that on freight or long 
trains there is a greater volume of air to control, a larger 
number of auxiliary reservoirs to recharge and it is more 
difficult to release the brakes than on a short train. 

STORAGE OF PRESSURES. 

The compressed air used on an engine and train is stored 
in the main reservoir, small drum, brake pipe, auxiliary 
reservoirs and signal line. 

Main reservoir pressure is stored in the main reservoir 
and its pipe connections, and is used to operate the different 
devices on the engine and for charging and recharging the 
brake pipe, auxiliary reservoirs and signal line. 

Chamber D pressure is stored in chamber D and the 
small drum. Its purposes are to allow the engineman to do 



AIR BRAKE OPERATION. 333 

gradual braking, hold the equalizing piston to its seat and 
operate the black hand of the air gauge. 

Brake pipe pressure is stored in the brake pipe, and is 
used to operate the pump governor of the D-8 brake valve, 
charge and recharge the auxiliary reservoirs, apply and 
release the brakes, and assist in applying the brakes in 
emergency applications with the old type quick action 
triple, and in service and emergency applications with the 
"K" triple valve. 

Auxiliary pressure is stored in the auxiliary reservoir ; 
its duty is to hold the slide valve to its seat, operate the 
quick action parts of the triple, set the brake and also to 
charge the water pressure on tourist cars that are so 
equipped. 

Signal line pressure is stored in the signal line and in 
chambers A and B of the signal valve. It is used to trans- 
mit signals from trainmen to enginemen. 

BEGINNING AND ENDING OF PRESSURES. 

Main reservoir pressure begins on top of both discharge 
valves ; it ends at the top of the rotary valve in the 
engineer's brake valve, and at the faces of all valves oper- 
ated by main reservoir pressure. 

In running position with the D-8 brake valve it ends at 
the main reservoir side of the excess pressure valve, at the 
main reservoir side of the feed valve with the G-6 brake 
valve, at the low pressure pump governor of the duplex 
on freight, if attached to the running feed port, and at the 
red hand of the air gauge and the high pressure governor. 

Straight air pressure begins at the straight air side of 
the reducing valve and ends underneath the application 
valve of the straight air brake valve. 

Signal line pressure begins at the signal line side of the 
signal reducing valve and ends at the first turned cut-off 



334 AIR BRAKE OPERATION. 

cock in the train, at the car discharge valves of the coaches 
and in chambers A and B of the signal valve. 

Chamber D pressure begins at the equalizing port and 
ends at the top of the equalizing piston, in the small drum 
and at the black hand of the air gauge. 

Brake pipe pressure begins in cavity C of the rotary 
valve and in the brake pipe side of the feed and excess 
pressure valves, and ends at the pump governor of the 
D-8 brake valve, underneath the brake pipe side of the 
equalizing piston, the first closed angle cock in the train, 
the conductor's valve of the coach or way car, the plain 
side of the triple piston and in chamber Y. 

Auxiliary pressure begins at the auxiliary side of the 
triple piston and ends in the auxiliary reservoir, the water 
pressure governor of Pullman and tourist cars, and the 
face of the slide valve. 



AIR BRAKE OPERATION. 335 

GENERAL INFORMATION RELATING TO 
AIR BRAKE PRAGTICE. 

Time Consumed in Charging. With a constant pres- 
sure of 70 pounds in the brake pipe, the auxiliary reservoirs 
of short trains should charge in about. 70 seconds but, owing 
to clogged strainers, feed grooves, the difference in the size 
of feed grooves and the capacity of auxiliary reservoirs, 
it ordinarily takes from 2 to 2^4 minutes, and on long 
trains from 5 to 10 minutes. An engineman should bear 
this in mind before releasing to make a second application, 
while charging the train at a terminal and before releasing 
to recharge while descending heavy grades. 

Air Gauge Indications. The black hand of the air 
gauge indicates the brake pipe pressure when the brake 
valve is in full release, running and lap positions, when 
chamber D and brake pipe pressures have equalized, and 
also at the beginning and ending of a brake pipe exhaust 
in a service application, but not during the brake pipe 
exhaust or in an emergency application. 

Equalization of Pressures. Brake pipe and auxiliary 
reservoir pressures are equal when both are charged and 
in lap position of the brake valve, but they are not the same 
when charging, applying or releasing the brakes, in an 
over-reduction or in an emergency application. 

Sources of Air to Brake Cylinders With Different 
Types of Triple Valves. The air that enters the brake 
cylinder passes from the auxiliary reservoir in service and 
emergency applications with the plain and quick action 
triple valves, from both the brake pipe and the auxiliary 
reservoir in an emergency application with the quick action 
triple, and from the brake pipe and auxiliary reservoirs in 
service and emergency applications with the "K" type 
triple valve. 



M6 air brake operation. 

Piston Travel. The proper piston travel is from 
6 to 9 inches on cars, tenders and engine trucks ; 2 to 4 
inches on cam driver brakes, and 4 to 6 inches with Amer- 
ican driver brakes. 

Slack Adjustment. Slack in the brake rigging is 
taken up on passenger cars by. means of turnbuckles, dead 
levers, or the patent slack adjuster ; on freight cars and 
tenders by dead levers, or bottom rods for inside connected 
brakes ; on cam driver brakes by lengthening the arms ; on 
truck brakes by lengthening the outside arm, and on the 
American driver brake by adjusting the screw bolt or turn- 
buckle. The shoes of the cam driver brakes are prevented 
from rubbing against the tires by means of the adjusting 
rods or springs. 

Braking Power. The braking power is dependent 
largely on the piston travel ; the shorter the piston travel, 
.the greater the braking power, and the higher the pressure 
at which the auxiliary reservoir and brake cylinder pres- 
sures will equalize; the longer * the piston travel, the lower 
the pressure at which they will equalize, and the weaker the 
braking power. 

With the same piston travel the holding power of the 
brakes will be alike on empty and loaded cars, but the 
empty car will be brought to a stop in less distance than 
the loaded car, this being due to the fact that the brakes 
must overcome the greater weight, in addition to the 
momentum of the loaded car. 

Driver and Tender Brakes. Poor driver and tender 
brakes have a tendency to increase the number of flat 
wheels on cars, as the cars must necessarily stop the 
engine, instead of the engine helping to stop the cars ; this 
causes the train brakes to be used more severely. 

It is of the utmost importance that the driver brakes 
be kept in good condition, as they are the most powerful 
brakes on the train and the most expensive. They also 



AIR BRAKE OPERATION. 337 

keep the tires worn down evenly, prevent the engine from 
pulling away from the tank, prevent break-in-twos near 
the head end of the train and keep the slack in the train 
well bunched. 

Wheels Sliding. Wheels generally slide at low and 
not at high speeds, as the friction between a wheel and 
brake shoe increases as the speed of the wheel decreases. 

"During cold weather an engineman should always 
examine the tank wheels before starting out, to see that no 
brake shoes are frozen to the wheels, which can be detected 
by moving the engine and watching the wheels to see that 
the} r revolve. 

The wheels on a passenger car are more liable to slide, 
than those on a freight car, as a passenger car has a 
braking power with an emergency application of 90 per 
cent of the light weight, while the braking power of empty 
freight cars is only 70 per cent of the light weight. 

Reductions and Applications. Many persons do not 
distinguish the difference between a reduction and an appli- 
cation. An application consists of any number of reduc- 
tions without releasing the brakes, and may be made several 
times during an application. 

Leakage Grooves. The purpose of the leakage 
grooves in the brake cylinder is to provide for leakages or 
slight reductions in brake pipe pressure which would cause 
the triple valve to move to service position, closing the 
triple exhaust. Any small volume of air that passes from 
the auxiliary reservoir to the brake cylinder can pass 
through the leakage grooves without forcing the piston out, 
and applying the brakes. These leakage grooves are from 
2.^/2 to $ l / 2 inches long and are usually placed on the side 
or top of the brake cylinder, on the pressure end, or where 
the piston lies when the brake is released. 

Forcing Pistons Past Leakage Grooves. In making 
a service application the first reduction should be sufficient 



338 AIR BRAKE OPERATION. 

to force the pistons past the leakage grooves; from 5 to 10 
pounds will he required, according to the length of the 
train. A slight reduction is sufficient for a short train, but 
a heavier one is necessary for a long train. 

Amount of Reduction. When making a service 
reduction with any given pressure the proportion it should 
be reduced to secure a full application of the brakes would, 
with a standard piston travel of 8 inches, be about two- 
sevenths of the brake pipe pressure, as the auxiliary reser- 
voir is usually about 2 Y / 2 times larger than the brake 
cylinder. 

A 10-pound reduction from a brake pipe pressure of 
65 pounds will not apply the brake with greater force than 
a 10-pound reduction from a 50-pound brake pipe pressure, 
as there is a pressure of only 10 pounds going to the brake 
cylinder, and it is above the equalization point for the two 
pressures. 

If a reduction of two-sevenths of the brake pipe pres- 
sure is made with an 8-inch piston travel and a 70-pound 
brake pipe pressure, the auxiliary reservoir, brake cylinder 
and brake pipe pressure will equalize at five-sevenths, or 
50 pounds. 

With a pressure of 35 pounds in the brake pipe and 
auxiliary reservoirs it would be necessary to make a reduc- 
tion of two-sevenths, or 10 pounds, with an 8-inch piston 
travel, in order to obtain full braking power of this pressure. 

A greater pressure can be obtained in the brake cylinder 
by carrying a higher brake pipe pressure, shortening the 
piston travel, or making an emergency application with the 
quick action triple valve, and by the use of the retaining 
valves in a second application with both service and emer- 
gency applications. 

Over-Reduction. An over-reduction is one in which 
the brake pipe pressure is reduced below the point at 
which the auxiliary reservoir and brake cylinders equalize, 



AIR BRAKE OPERATION. 339 

It results in a useless waste of brake pipe air and an irregu- 
lar and often a difficult release of the brakes. Also, if there 
is a defective packing ring and gasket in the triple valve on 
which the triple piston is seated, air can feed from the 
auxiliary reservoir to the brake pipe, and decrease the 
braking power of the car having the defective packing ring. 

Service Applications. One application of the brakes 
is all that is necessary to stop any train, but it is advisable 
on passenger trains to make two applications in order to 
insure smooth and accurate stops, without danger of wheel 
sliding. More than one application is not advisable on 
freight trains on account of the uneven piston travel. On 
a long freight train with the old style triple valve, the head 
brakes will release before the rear brakes, allowing the slack 
to run out, with consequent danger of breaking in two. 
More than two applications should not be made in any case, 
as sufficient time would not be given between applications 
for the auxiliary reservoirs to recharge, thus decreasing the 
braking power. 

Emergency Applications. An emergency application 
should be made only in cases of actual emergency to prevent 
an accident. In making an emergency application the handle 
of the brake valve should be placed in full emergency posi- 
tion as quickly as possible and left there, and a flow of sand 
started at once. It is possible to get emergency action of 
the brakes without losing all brake pipe air, but it is not 
good practice to attempt to save air at times of pressing 
danger, and is not advocated under any circumstances. If 
it is practiced when several cars which are cut out are 
placed together, only the brakes ahead of these cars will go 
into emergency application, while those behind them will 
apply with only partial service action. If the brake valve 
is left in full emergency position a full service application 
will be had on all cars back of the cut-out cars, obstructed 
hose, or partly closed angle cock, in addition to full emer- 



340 AIR BRAKE OPERATION. 

gency application on all cars ahead of them. The greatest 
possibility of danger is that an engineman may thoughtlessly 
bring the brake valve past lap position too far, placing it in 
running position and thus releasing the brakes. Also if the 
brake valve were moved to lap position too quickly the 
sudden stoppage of air in the head end of the brake pipe 
would release the head brakes, which might also result in 
parting the train. 

Releasing. To release the brakes it is necessary to 
raise the brake pipe pressure the entire length of the 
train above the pressure in the auxiliary, this generally 
being sufficient to overcome the frictional resistance of 
the triple piston and slide valve. If, however, an over- 
reduction has been made it will be necessary to increase 
the brake pipe pressure the amount of the over-reduc- 
tion, plus the amount required to overcome the resist- 
ance of the triple piston and slide valve. 

When it is desired to release the brakes the brake 
valve handle should be moved to full release position 
regardless of the length of the train. When all the brakes 
are released, and before they are overcharged, the brake 
valve handle should be returned to running position. The 
length of time required for releasing depends entirely on 
the length of the train, the amount of the 'reduction and 
the size of the main reservoir. Ordinarily one-half second 
for each car is sufficient for the release of all brakes. 

An engineman should learn to release the brakes by 
watching the air gauge. When the brake valve handle 
is placed in release position the main reservoir and brake 
pipe pressures should practically equalize, but not over- 
charge. On short trains this equalization takes place 
very rapidly ; consequently the brake valve handle should 
be returned to running position before overcharging takes 
place. On long trains equalization takes place slowly, 
the rear end of the train receiving its increase of pressure 



AIR BRAKE OPERATION. 341 

more gradually, due partly to frictional resistance in the 
brake pipe. 

Sufficient Time for Releasing. Sufficient time should 
be given for all brakes to release, and the brake valve 
handle should be allowed to remain in release position 
longer with long than with short trains. On trains of 
over 30 cars, the head brakes, being nearest the engine, 
charge more rapidly than the rear ones, due to the pres- 
sure being greater in the head end of the brake pipe 
than in the rear end. 

During the time that the pressure is reaching the rear 
end of the brake pipe on long trains, and the brake valve 
handle is returning to running position, the brake pipe 
air equalizes from the head to the rear end, causing the 
head brakes to reapply, which makes it necessary to 
again place the brake valve in release position for a few 
seconds, after which it should be returned to running 
position, which will release the light application of the 
head brakes. A double release is thus required on long 
trains to insure a full release of all brakes. 

Testing for Leaks. When testing for leaks in the air 
brake equipment, especially on the engine and tender, a 
brake pipe reduction of about 15 pounds should be made, 
the brake valve placed in lap position and the air pump 
shut off. If the red hand falls and the black hand remains 
stationary it is a main reservoir leak, but if the black- 
hand falls and the brake does not release it is a brake 
pipe leak. If the black hand raises and the brake releases 
it indicates a leak at gasket 32, or a leaky rotary valve. 
If the brake releases and the black hand falls it indicates 
a leaky auxiliary reservoir, but if the brake releases and 
the black hand remains stationary it indicates a leaky 
graduating valve. If the brake leaks off and there is no 
sound at the triple exhaust there is a leak in the pipe 
connection leading from the triple valve to the brake 



342 AIR BRAKE OPERATION. 

cylinder or from one driving brake cylinder to the other, 
a leak at the leather gasket in the brake cylinder, or a 
defect in the brake cylinder or head. If the engine is 
equipped with the high speed reducing valve, and the 
brake leaks off, it may be due to a defective valve, or a 
leak in the pipe connection leading to it. 

The leaks enumerated can also be detected by making 
a service application of the brakes and examining all pipe 
connections and joints with a torch while the brakes are 
applied. 

Observing the Air Gauge. It is of more importance 
to have a good light on the air than on the steam gauge, 
as the steam pressure is indicated by the working of the 
engine, while the air gauge affords the only means of 
ascertaining the air pressure. A clear view of the air 
gauge at night is very important and should be given 
greater attention than is usually accorded it. 

An engineman should look at his air gauge frequently 
and should always make it a practice to notice it when 
approaching railroad crossings, junctions, drawbridges, 
stations, meeting points, before making the running test 
and before passing through dangerous localities. 

Testing Air Gauge. The air gauge can be tested by 
placing the engineer's brake valve in full release position, 
as this places the main reservoir, brake pipe and chamber 
D in free communication with one another, and allows 
their pressures to equalize. As the black hand of the 
air gauge is connected with chamber D and the red hand 
with the main reservoir, practically the same pressure 
should be registered by both hands of the gauge. If 
there is a difference of not to exceed 3 pounds the gauge 
may be considered all right ; if the difference is greater 
than this it should be reported for testing. 

Number of Air Cars in Train. All working air brake 
cars in a train should be in service and must represent 



AIR BRAKE OPERATION. 343 

at least 75 per cent of the total number of cars in the 
train. 

By making a five or six-pound reduction an engine- 
man can tell approximately how many cars are coupled 
up by the length and strength of the brake pipe exhaust, 
but he cannot tell how many cars are cut in or working. 

When the brake valve handle is moved from lap to 
release position and a blow occurs from the brake pipe 
exhaust it would indicate that there were only a few 
or no cars cut in. The short brake pipe would be 
charged sooner than chamber D, which would raise the 
equalizing piston, causing the discharge of brake pipe 
pressure. 

Defective Triple or Obstructions in Brake Pipe. 
When making a service reduction an engineman can 
determine whether the brakes apply in emergency by 
a sudden momentary stoppage of brake pipe exhaust, 
when the brake valve handle is in service position ; he 
also can detect a partly closed angle cock or collapsed 
hose, as there would be a full blow of air from the brake 
pipe exhaust at first, and then the blow will partly cease, 
due to the air passing slowly past the obstruction. 

Terminal Tests — Freight Trains. Before starting on 
a trip the air brakes should be tested, which is a joint 
duty of the engineman and the trainmen. The engine- 
man should have full excess pressure in the main reser- 
voir when backing up to couple on the train, and while 
the engine is being coupled to the train he should make 
a reduction of about 14 pounds in brake pipe pressure, 
which will block an emergency application when the air 
is cut in. 

The brakeman should open the angle cock on the 
tender and note whether a good blast of air is secured 
before making the hose coupling to the engine, and then 
couple up the hose and open the angle cock gradually. 



344 AIR BRAKE OPERATION. 

He should then notify the engineman that the air is 
cut in. 

The engineman should then place the brake valve 
handle in full release position and allow it to remain in 
this position until the main reservoir and brake pipe 
pressures have equalized below 70 pounds, after v/hich, 
with the G-6 brake valve, it should be placed in running 
position. If the D-8 brake valve is used it should be left 
in full release until the brake pipe pressure reaches 70 
pounds, while with the New York brake valve it may 
be placed in either full release or running position. 

While the train is being charged the brakeman should 
pass alongside of it, inspecting the brake rigging and not- 
ing whether there are any brake pipe or auxiliary leaks : 
if any are found they should be remedied ; if defective 
hose or gaskets are found they should be replaced with 
new ones. 

When the train is charged and the engineman. is satis- 
fied that the brake system is reasonably free from leaks, 
the rear brakeman, stationed at the rear air car, should 
transmit the signal "apply air brakes" to the head brake- 
man, who should repeat the signal to the engineman, who 
will make a 25-pound brake pipe reduction, and then 
place the brake valve in lap position. The engineman 
should also note the length and strength of the brake 
pipe exhaust, which will indicate whether any triple 
applied in quick action, the length of the brake pipe and 
whether there is a partly closed angle cock or an 
obstruction in the brake pipe. 

After a full reduction has been made by the engine- 
man thus applying the brakes it is the duty of the head 
and rear brakemen to walk toward one another, inspect- 
ing the brake on each car to see that it applies and holds, 
noting the piston travel, and looking for brake pipe, 
cylinder and auxiliary leaks. When the brakemen meet 



AIR BRAKE OPERATION. 345 

they should signal the engineman to release the brakes, 
and then return to their respective ends of the train, 
noting that all brakes have released and that no shoes 
are frozen to the wheels in cold weather. If any brake 
fails to release it may be cut out, carded and the auxiliary 
reservoir drained of its air. After reaching their 
rspective ends of the train the brakeman should notify 
the conductor of the condition of the train brakes and the 
number of cars in working order. The conductor should 
then in turn notify the engineman of the condition of the 
brakes, the number of loads and empties, their location 
in the train and the amount of tonnage, so that the 
engineman can use his judgment accordingly when 
using the brakes. 

Passenger Train Tests. When making a test on a 
passenger train at a terminal the same rule should be 
followed as with a freight train, but in addition the air 
signal line leading to the air whistle must be tested. The 
brakeman should pass through the train, testing the car 
discharge valve of each coach. He should then give the 
engineman the hand signal to apply the brakes from 
the head end of the train, and then pass alongside the 
train, inspecting the brakes to see that all apply. After 
reaching the rear of the train he should signal the engine- 
man to release the brakes, by giving four distinct blasts 
of the air whistle, and then return to the head of the 
train, noting that all brakes release. 

Running Test. When a train leaves its terminal, or 
a change is made in the make-up of a train, the engine- 
man should make a running test of the brakes after the 
train has moved a train-length, by applying the brakes 
with the throttle open. As soon as the brakes are left 
to take hold they should be released. This not only 
assures the engineman that the brakes are cut in, but 
also indicates how they act and hold. While this test 



346 AIR BRAKE OPERATION. 

is being made the engineman should also observe the 
brake pipe exhaust. 

This test should be repeated when engmes are 
changed, adding a double header, after long delays at 
any point on the road, when air cars are added to or set 
out from the train, when the engine is cut off and when 
the train is cut at a crossing. The head brakeman 
should make the terminal test on cars picked up, while 
the rear brakeman or the conductor should see that the 
brakes on the rear air cars are applied and released from 
the engine. 

A full reduction should always be made when making 
a test, as a lighter one of 5 or 6 pounds would not be 
sufficient to force the pistons past the leakage grooves 
with a long train. Also with a light reduction the 
brakes on cars that had not been fully charged would 
not apply, and it would not be possible to get full piston 
travel, as would be the case with a full service reduction. 

If one triple valve goes to emergency position all 
others will follow, as a sudden reduction of brake pipe 
pressure rushing to the brake cylinder will cause the 
other triples of either type to go to emergency. 

Emergency Applications Not to Be Made When Test- 
ing. Emergency applications must not be made when 
testing brakes, for the reason that ordinary braking 
should not be done in this manner as it causes an unnec- 
essary strain on the brake rigging, and it will be impos- 
sible to detect any defective triple valve in the train, as 
some brakes would set in emergency that would not set 
in a service application. It would also cause a waste of 
brake pipe air, making it difficult to release the brakes. 

Detecting Defective Triples. When testing brakes 
with the train standing, and any brake in the train sets 
in quick action, it will cause a momentary stoppage of 
the brake pipe exhaust, as the brake pipe pressure would 



AIR BRAKE OPERATION. 347 

be vented to the brake cylinder of each car, reducing the 
pressure below that in chamber D, which in turn would 
seat the equalizing piston. 

Locating Defective Triples. To locate a defective 
quick action triple on a train of from 5 to 10 cars the 
engineman should make a 5-pound brake pipe reduction, 
and the car on which the brake does not set should be 
located. When the car is located a further reduction 
should be made and if the brake on this particular car 
sets quick action it should be cut out and carded. The 
entire train should then be recharged and another test 
made, to ascertain that the defective triple has been 
found. On a long train it would be necessary to make 
a sectional test in order to locate the car with the 
defective triple, cutting in 10 cars with each test and 
proceeding as above described. 

Inspect All Brakes. When making a thorough test it 
is necessary to hold the brakes set until the trainmen 
have sufficient time to inspect all the brakes thoroughly. 
The longer a brake remains applied the more certain an 
engineman can be that it will hold for a long, hard stop. 
A brake that will not remain applied for a minute or 
longer is considered a poor brake and should be carded. 

Releasing Before Uncoupling. The air brakes should 
be released before uncoupling, which prevents the brake 
shoes from freezing to the wheels and the triples from 
freezing in set position in cold weather. If the brakes 
were left applied when cutting off to take water and coal 
there would be an additional reduction from the brake 
pipe by leakage, and it would require a larger volume 
of air to release the brakes when the engine was 
recoupled ; also if the brakes released on a grade, the 
slack would run in, which might start the train. The 
air brakes should not be relied upon for holding a train 
on grades when the engine is cut off. 



348 AIR BRAKE OPERATION. 

Loss of Excess Pressure. If the handle of the D-8 
brake valve is left in. full release position too long and 
then brought back to running position the excess pressure 
would be lost, and if there were any leaks in the brake 
pipe they would cause the brakes to apply before suffi- 
cient excess pressure was accumulated in the main reser- 
voir to unseat the excess pressure' valve and supply the 
brake pipe. 

If the brakes apply with the handle of the D-8 brake 
valve in running position after a release of the brakes 
has been made it would be due to a lack of excess pres- 
sure, as with this type of valve jn running position it is 
necessary to obtain excess pressure in the main reservoir 
before air can pass into the brake pipe. If care is taken 
to prevent the loss of excess pressure when making the 
release this trouble will not be experienced. 

Overcharging. If the G-6 brake valve were left in 
release position too long the excess pressure in the main 
reservoir would be lost and the brake pipe and auxiliary 
reservoirs overcharged, and when the brake valve was 
placed in running position there would have to be a leak 
in the brake pipe or the pressure in the brake pipe 
reduced below that for which the feed valve was set 
before any air could pass from the main reservoir to the 
brake pipe, which would cause the brakes to apply. This 
difficulty would not be experienced with the B2 and the 
B3 New York brake valves, as the controllers prevent 
the brake pipe from becoming overcharged in all posi- 
tions of the brake valve. 

With the D-8 brake valve the brake pipe pressure is 
regulated by the pump governor, and in lap position 
communication between the main reservoir and the 
brake pipe is closed and the governor does not control 
the pump. Consequently when the brake valve is left 
in lap position too long the pump will operate until the 



AIR BRAKE OPERATION. 349 

main reservoir pressure is equal to the steam pressure 
of the boiler. When the brake valve is placed in release 
position this high excess pressure is liable to result in 
bursting of an air hose, overcharging the brake pipe 
and auxiliary reservoirs, and stopping the pump, which 
will not go to work until the brake pipe pressure is 
reduced, or has leaked down below the pressure at which 
the governor is set, causing the brakes to apply. 

Speed of Pump Descending Grades. With the D-8 
brake valve the pump should not be run at a high rate 
of speed while descending heavy grades, but the speed 
of all pumps should be sufficient to maintain the proper 
excess pressure in the main reservoir required to insure 
a prompt release of brakes and a rapid recharge of brake 
pipe and auxiliary reservoir pressures. 

Failure of Brakes to Release and Causes for Brakes 
Dragging. When the brakes drag or fail to release it is 
usually due to lack of sufficient excess pressure, espe- 
cially on long trains, failing to make a second release 
on long trains, failure to leave the brake valve handle 
in release position a sufficient length of time, or making 
light reductions and releasing. The last is one of the 
most frequent causes of brakes sticking. 

Another cause is the overcharging of the brake pipe, 
which usually results from leaving the brake valve 
handle in release position too long when releasing, thus 
allowing both the brake pipe . and auxiliary reservoirs 
to become overcharged. In this event the leakage from 
the brake pipe is not supplied, as with the D-8 and the 
New York brake valves the excess pressure valve closes 
until excess pressure has again accumulated in the main 
reservoir. With the F-6 and G-6 brake valves, if the 
brake pipe pressure is raised above 70 pounds, the feed 
valve closes and leakage will reduce the pressure in the 



35o AIR BRAKE OPERATION. 

brake pipe until it falls below 70 pounds. Until the 
pressure is reducd to this point the brakes will drag. 

Another frequent cause of brakes dragging results 
from enginemen moving the brake valve handle from 
running to release position in trying to release imaginary 
brake dragging. If this is done too often the brake pipe 
and auxiliary reservoirs will become overcharged and 
the brake dragging will become actual instead of 
imaginary. 

A heavy leakage from the brake pipe will also cause 
brakes to drag. This leakage usually occurs when trains 
are stretched after standing, particularly in cold weather 
when the air hose becomes frozen. 

Leaks that result in applying the brakes may arise 
from a defective governor with a D-8 brake valve, or 
defective feed valves with the G-6 brake valve, where 
either of these interfere with the supply of air to the 
brake pipe. The failure of the governor to act, thus 
holding the pump idle, or the feed valve shutting off 
the supply of air from the brake pipe, will give the 
leakage a chance to apply the brakes. 

How to Release Brakes That Are Sticking. When 
brakes are dragging they can be successfully released 
by using one of the following methods : If the brake 
pipe pressure is below normal (as it will be if leakage 
applies the brakes), and the proper excess pressure is 
maintained in the main reservoir and if there is sufficient 
room in the brake pipe for the excess pressure without 
overcharging, the brake valve handle should be placed 
in full release position, as in making the ordinary release. 
But if the brake pipe pressure is normal and the brakes 
are applied (which may occur with an improper release), 
the brake valve should be placed in lap position and left 
there until full excess pressure is obtained, when a 
10-pound reduction should be made and the brakes 



AIR BRAKE OPERATION. 351 

released. If the brake pipe pressure is below normal, 
and there is no excess pressure in the main reservoir, 
the brake valve should be placed in lap position until the 
necessary excess pressure is accumulated, when the 
brakes should be released. 

An engineman should never attempt to pump the 
brakes off or try to release them when the brake pipe 
pressure is up to standard, as it will result in the brake 
pipe and auxiliary reservoirs becoming overcharged, and 
will cause all brakes to apply. 

Two-Mile Test. The two-mile running test should 
be made before descending heavy grades and when 
approaching terminals, meeting points, railroad crossings, 
junction points, interlocking plants, ends of double 
tracks and other dangerous places where a stop may 
be required. This test is made by making a sufficient 
reduction of brake pipe pressure on freight trains to 
raise the equalizing piston with a 3 or 4-pound ^eduction, 
and noting the length and strength of the brake pipe 
exhaust. On passenger trains a 10-pound reduction 
should be made and the engineman should feel the brakes 
take hold, in addition to noting the length and strength 
of the brake pipe exhaust, and then release the brakes. 

Automatic Application. If the brake suddenly applies 
without a reduction being made by the engineman the 
engine should be shut off and the handle of the brake 
valve placed in lap position at once. The application 
of the brakes mav result from a bursted hose, the train 
parting, or the conductor's valve being opened. Care 
should be exercised to keep the detached parts of the 
train together to prevent as much damage as possible 
and to maintain the main reservoir pressure so that it 
will be available for releasing the brakes when necessary. 

When a train breaks in two and the sections come to 
a stop, or in the case of a bursted hose, the brake valve 



352 AIR BRAKE OPERATION. 

should be placed in running position in order to ascertain 
whether the brake pipe is still open, which would be 
indicated by the air gauge. The brake valve should be 
kept moving from running to lap position until the 
defective hose or leak is located. By handling the brake 
valve in this manner the defect can easily be located 
by the trainmen from the intermittent sound of the 
escaping air. If the black hand of the air gauge raises 
when the brake valve is in running position it indicates 
that the defect has been located and the angle cock 
closed just ahead of it. The brakes should then be 
released, the brake valve placed in lap position and 
excess pressure obtained in the main reservoir, so that 
the brakes on the rear cars may be released when the 
defective hose has been replaced or the train has been 
recoupled. 

If, after coupling up, it is impossible to release all 
the brakes, the brake valve should be placed in full 
release position, allowing the pump to force air directly 
into the brake pipe. When the pressure in the brake 
pipe reaches 58 or 60 pounds the brake valve should 
be placed in lap position and left until the full amount 
of excess pressure has accumulated in the main reservoir, 
when the brakes can be released in the usual manner. 

Use of Tail Hose. When backing up a train with the 
tail hose in use the brake pipe should first be blown out 
before attaching the tail hose, the terminal or road test 
of the air brakes should be made by the engineman and 
a test of the tail hose should then be made by the train- 
men stationed on the rear car. The latter test should 
be made after the train is in motion, the first application 
being made about 200 feet or three car-lengths from 
the starting point. If a slow-down is not felt within 
this distance the engineman should bring the train to 
a stop and ascertain why the test has not been made. 



AIR BRAKE OPERATION. 353 

The engineer's brake valve should be carried in running 
position, and not. placed in lap position, to assist in 
making an application from the tail hose. Following 
either a slow-down or a stop, when a signal to continue 
backing is given, the brake valve should be moved to 
release position, as in making a regular brake release, to 
insure a release of all brakes. The engineman should 
apply the automatic brakes whenever it is required to 
insure the safety of the train, in the absence of a suffi- 
cient application from the tail hose. 

Trainmen should understand that in operating the 
brakes with the tail hose, and when the brake valve is in 
•running position, the valve of the tail hose should be 
opened slowly and the opening gradually increased until 
the valve is wide open, or the train has slowed down as 
much as desired or has been brought to a stop. This 
valve should not be opened and closed. If the applica- 
tion has been too hard the closing of the tail hose valve 
will allow the brakes to release and recharge. The 
rapidity with which the valve is opened should be deter- 
mined by the speed, the length of the train and the 
distance within which it must be stopped. In cases of 
emergency the valve should be instantly opened to its 
full extent. On grades where a train will not stand with 
brakes released it should be held by admitting a little 
steam to the cylinders with the engine reversed. 

Two or More Engines Coupled. When two or more 
engines are coupled together the engineman on the 
leading engine should do the braking, as his view is not 
obstructed, and he is able to use better judgment in 
handling the brakes. 

Switching. In doing switching with an air brake 
train, the braking should be done in service with the 
automatic brake valve, provided the air brake cars are 
coupled up and cut in. If they are not coupled up and 



354 AIR BRAKE OPERATION. . 

cut in the independent or straight air brake valve should 
be used. When air cars are picked up and added to the 
train, or when the engine is coupled to cars that are 
to be moved quickly, it is a good plan to apply and 
release the brakes on the engine several times while 
backing up the cars. The brake valve should then be 
placed in lap position until a high excess pressure is 
accumulated in the main reservoir, the cars coupled 
to and the angle cocks turned so that the cars are cut 
in. This reduces the pressure in the auxiliary reservoirs 
of the engine and tender and whatever cars are coupled 
to the engine, so that when the additional air brake cars 
are coupled to it it will take but a short time for all 
brakes to be released, allowing the train to proceed. 
Otherwise the amount of air required to charge the added 
cars would be so great that the brakes on the engine, 
tender and attached cars would remain applied, and it 
would be impossible to proceed until the brake pipe 
pressure could be raised above the equalized pressure. 

The purpose of making these reductions and accumu- 
lating excess pressure in the main reservoir is to enable 
the engineman to move the cars and charge them while 
moving before they are coupled to the train. 

Before the brakes on the balance of the train are 
cut in the engineman should reduce the pressure suffi- 
ciently to block quick action. After the signal is given 
that all cars are cut in, a prompt release of all brakes 
should be made, and when the brake pipe and auxiliary 
reservoirs are again charged, the usual terminal test 
should be made on the cars picked up. It should also be 
noted whether the brakes on the rear air car applied and 
released properly. 

Reducing Speed When Approaching Descending 
Grades. When approaching long, descending grades the 
speed of the train should be checked, full pressure 



AIR BRAKE OPERATION. 355 

accumulated and the brakes applied in time. An engine- 
man should not wait until a full application is necessary 
to check the train, as the speed may not be reduced 
sufficiently by the time the brakes require recharging. 
A moderate application should be made in time, and the 
trainmen should see that the required number of 
retaining valves are closed whenever the retainers are 
to be used. 

Recharging When Descending Grades. An engineman 
should always plan to recharge the brakes on a let-up, 
where grades are not steep, or while passing around 
curves, as by so doing the train will not gain a speed 
beyond control during the time the brakes are being- 
recharged. 

When recharging, the brake valve should be placed 
in full release position and allowed to remain there until 
both hands of the air gauge are just past the 70-pound 
mark. With the retaining valves in use the engineman 
should remember .that a light reduction Avill be much 
more effective than if the retainers were not in use. For 
example, if a 5-pound reduction is made with the retainers 
not in use a pressure of about 12 pounds is obtained in 
the brake cvlinders, while with the retainers closed a 
pressure of about 15 pounds is obtained when making 
two or more applications, the extra braking power being 
due to the pressure retained in the brake cylinder by the 
retaining valves. 

Minimum Reductions. A reduction of not less than 
5 or 6 pounds should always be made, even when the 
retaining valves are in use, as some of them may be out 
of order and fail to retain any pressure in the brake 
cylinder and, unless a sufficiently heavy reduction to carry 
the pistons past the leakage grooves is made, no braking 
power will be obtained from the cars having defective 
retainers. 



356 AIR BRAKE OPERATION. 

Loss of Braking Power. An engineman should not 
place too much reliance on his brakes and should watch 
the air gauge closely. A small leak from the brake pipe, 
after making the first reduction, will allow just enough 
air to leak away to make a smooth stop. But if the brake 
pipe air has gradually leaked away (from any cause) 
without a reduction having been made by the engineman, 
it is difficult to gain control of the train, and it cannot 
be stopped by air until the brakes have been recharged. 
This would require considerable time and probably by 
the time the brake pipe and auxiliary reservoirs were 
recharged control of the train would be lost. 

Alternating Engine and Train Brakes. If the engine 
is equipped with the combined automatic and straight 
air brakes, the ET equipment, the New York air brakes, 
or other devices to maintain the driver brake pressure, 
the straight air feed can be used to assist in holding the 
train while recharging the automatic brakes. Engines 
equipped with the combined automatic and straight air 
brakes are also equipped with grade bleed cocks, which 
should be open on grade work, thus allowing the auto- 
matic pressure of the driver and tender brakes to escape. 
While recharging the brake pipe and auxiliary reservoirs 
the independent or straight air brakes should be applied. 
The alternate use of the automatic brakes, the straight 
air and retaining valves is for the purpose of preventing 
tires from becoming loose or wheels overheated. 

Use of Hand Brakes. Hand brakes should be used 
on non-air cars of a train only upon a signal for brakes, 
and when a train consisting of part air cars is backing 
the hand brakes should always be used to furnish most 
of the braking power required. When the engineman 
requires additional braking power on account of lack of 
sufficient air brake cars the hand brakes immediately 
behind the air cars should be used when going ahead. 



AIR BRAKE OPERATION. 357 

The hand brakes should also be used when a car is set 
on a siding and when a train is left standing on a grade, 
or any other place where there is a possibility of cars 
starting. 

Part Air Brake Freight Trains. To ordinarily apply 
and release the brakes on a freight train consisting of 
part air brake cars the engineman should shut oft" the 
engine throttle and allow the engine to bunch the slack 
of the train. He should then make a sufficient reduction 
to move the pistons past the leakage grooves and further 
allow the slack to bunch. He should then make sufficient 
reductions to bring the train to a stop, and release the 
brakes just as the train stops, in order that the brakes 
on the air cars may be entirely released before the slack 
of the non-air cars can run out, thus avoiding a parting 
of the train. If the engine is equipped with the ET 
equipment, combined automatic and straight air brake, 
or the New York B2 or B3 equipment, the straight air 
brake can be applied, the automatic brakes released and 
the driver and tender brakes graduated off without 
causing any shock to the train. 

All Air Brake Freight Trains. To apply and release 
the brakes on a full air brake freight train the engineman 
should shut off the throttle and make sufficient reductions 
of from 5 to 10 pounds, according to the length of the 
train. Care should be taken not to make the reductions 
too heavy, or serious damage may result from the rapid 
bunching of the train. It should be remembered that 
the reduction necessary to force the pistons past the 
leakage grooves varies according to the length of the 
train. With a train consisting of 20 cars, or less, a 
5-pound reduction will be sufficient. One pound should 
be added to this amount for each additional 10 cars added 
to the train. Any further reductions should vary in 
amount according to the length of the train, in the same 



358 AIR BRAKE OPERATION. 

proportion as the first reduction, and the intervals 
between reductions are alsb dependent on the length of 
the train. 

If one reduction is followed by another before the 
brake pipe exhaust ceases the two reductions will act as 
one. The longer the train, the longer the brake pipe 
exhaust will blow ; consequently, a longer interval must 
be allowed between reductions on long trains than with 
short ones. When the speed of long freight trains is 
reduced to 10 or 15 miles per hour, and the engineman 
desires to release the brakes before stopping, unless the 
speed of the train or the lay of the track is such that 
there is no danger of parting the train, it would be better 
policy to come to a full stop before releasing. If, how- 
ever, the engine were equipped with the combined 
straight air and automatic brakes, ET equipment, or 
New York brake, the engine and tender brakes can be 
applied and the automatic brakes released without danger 
of parting the train, even at the slowest speeds. 

Empty Cars Ahead and Loads on the Rear of Train. 
If a train consists of empty cars ahead and loads behind, 
the engineman should shut off the engine throttle, 
allowing the engine to bunch the slack, and then make a 
sufficient reduction, according to the length of the train, 
to force the pistons past the leakage grooves. When 
the brake pipe exhaust has ceased and the slack is 
bunched, another reduction should be made to bring the 
train to a stop. Full excess pressure should be accumu- 
lated in the main reservoir before releasing the brakes. 

Loads Ahead and Empties on the Rear. If an air 
brake train consists of loads ahead and empties behind a 
sufficient reduction should be made to force the pistons 
past the leakage grooves before shutting off the engine, 
thus keeping the train stretched. A sufficient reduction 



AIR BRAKE OPERATION. 359 

to bring the train to a stop should then be made, and 
the brakes released. 

Reversing Engine. While the driver brakes are 
applied the engine should never be reversed with the 
expectation of making a shorter stop than can be made 
with the brakes alone. For if this is done the driving 
wheels are almost sure to lock, and then almost the 
entire retarding power of the engine has been lost, as the 
steam cylinders are acting as air compressors, and this 
force exerted on the drivers with the air brakes applied 
would cause them to lock and slide. In close quarters 
there is a tendency among enginemen to reverse the 
engine in addition to applying the brakes. If this action 
has not been the direct cause of many wrecks it certainly 
has not prevented any, unless the driver brakes had lost 
their braking power through leakage immediately after 
the application was made. The only time when reversing 
is of advantage is when the engine is equipped with a 
poor driver brake or none at all. 

Drivers Sliding. If in making a stop with a heavy 
freight train the drivers begin to slide, and it is not 
advisable to release the brakes for fear of breaking in 
two, the reverse lever should be placed in full gear in 
the direction in which the engine is moving, and the 
throttle opened. This will usually start the drivers, but 
if it fails to do so the brake valve should be placed in 
release position, as it is better to take chances of pulling 
out a drawbar rather than flattening the driver tires. 

If the drivers slide on an engine equipped with the 
combined automatic and straight air brakes the grade 
bleed cock should be opened, which will release the 
driver brakes ; if with the ET equipment, the independent 
brake valve should be placed in release position, and if 
the New York air brake is used, the lever safety valve 
should be opened. 



360 AIR BRAKE OPERATION. 

Use of Sand. Sand on the rail is used for two 
purposes ; to cause the wheels to grip the rail and to 
increase the friction between the brake shoe and the 
wheel, thus lessening the danger of wheels being flat- 
tened by sliding and also making a shorter stop. To use 
sand properly requires good judgment. When it is 
desired to make a quick stop, a stop on a descending 
grade, or a stop on a slippery rail, and a heavy applica- 
tion is intended, the air sander should be opened and the 
rail under the entire train sanded before a reduction in 
brake pipe pressure is made. The sand should then be 
used lightly and continuously until the train is brought to 
a stop. Sand should not be used after the wheels begin 
to slide, as they will not start revolving again, and the 
resulting flat spots on the wheels will be worn larger. 
It is bad practice when stopping a train to use the sand 
after an application has been made, as some of the wheels 
may be sliding, and flat spots will be the result. Tilts 
applies to freight as well as passenger trains. 

Number of Applications. An engineman should plan 
to make all ordinary stops of passenger trains with two 
applications of the brakes. This is practiced on the 
majority of roads and by the exercise of good judgment 
and care, accurate and smooth stops can be made. The 
first application should be sufficient to reduce the speed 
to 15 or 18 miles per hour. The brakes should then be 
released by placing the brake valve in full release posi- 
tion, and the brakes recharged if the time is sufficient; 
if not, the brake valve should be placed in lap position 
and a second light application made t'o stop the train at 
the desired point. If the speed of the train is low, one 
application will be sufficient, as one or two light reduc- 
tions with low cylinder pressure will make the stop 
nicely. 

The brake valve is placed in lap position after the 



AIR BRAKE OPERATION. 361 

first application in order to prevent surplus air from 
entering the brake pipe. The air admitted should be just 
sufficient to raise the brake pipe pressure enough to 
release the brakes without recharging the auxiliary reser- 
voirs. The feed grooves in the triple valves are compar- 
atively small, and when the brake pipe is charged higher 
than the auxiliaries, unless there is sufficient time for the 
two pressures to equalize before making the second 
application, the excessive brake pipe pressure must be 
reduced an additional amount before the second applica- 
tion can be made effective. This requires considerable 
time, as well as distance, and a heavy reduction would 
be necessary to make the second application, which 
would probably result in an inaccurate and disagreeable 
stop. 

In making a stop with a passenger train on a slippery 
rail the engineman should shut off the engine at a reason- 
able distance for making the stop, and apply sand to the 
rail for the full length of the train before applying the 
brakes. A sufficient reduction should then be made to 
bring the speed of the train down to 15 or 18 miles per 
hour, and the brake valve moved to release position and 
left there ordinarily one-half second for each car in the 
train, in order to insure a release of all brakes. The 
brake valve should then be placed in lap position, so 
that the final stop may be made with a light application 
and low brake cylinder pressure, the sander being 
allowed to run until the train is fully stopped. If the 
conditons are such that the sanders cannot be depended 
upon, as with a side wind or the sanders stopped up, the 
braking should be done as described, but it would be 
necessary to make a heavy application at high speed. 
If a spot stop is necessary a third application is advisable. 

On a passenger train running at high speed a moder- 
ate reduction of at least 10 pounds should be made to 



362 AIR BRAKE OPERATION. 

prevent the train from lurching as the engine and cars 
strike a curve. The application should be made an 
engine-length before reaching the curve, and the brakes 
allowed to remain applied until the last car is well on 
the curve, when the release can be made, as the lurch 
is over as soon as the flanges of the wheels crowd the 
outer rail. On short curves the brakes should be held 
on until the train is entirely off the curve. 

Approaching Dangerous Localities. When approach- 
ing dangerous points where switch engines are employed, 
interlocking plants, railroad crossings, drawbridges, 
meeting points and yards, the brake pipe and auxiliary 
reservoirs should be fully charged between the first and 
second applications, so that in case of an emergency there 
would be ample braking power available. 

Final Stops— Passenger Trains. When making a stop 
with a passenger train of less than 10 cars the brakes 
should be released just before the train stops, as the 
brakes of passenger cars are usually hung from the 
trucks, and when the brakes are applied the trucks tilt. 
If they are held on until the stop is made the movement 
of the trucks when leveling themselves causes a back- 
ward lurch of the train that is very disagreeable to 
passengers. This lurch is avoided by releasing and 
allowing the trucks to adjust themselves just before the 
stop is completed. The time at which the final release 
should be made depends on the amount of the brake 
application, as the harder they are applied the longer it 
will take to release them. When a train consists of 10 
cars or over the brakes should be held on with the second 
application until the train is brought to a full stop, unless 
the engine is equipped with a retainer, straight air brake, 
ET equipment, or the New York improved brake equip- 
ment. 

Service Applications With High Speed Pressure. 



AIR BRAKE OPERATION. 363 

With full high speed brake pipe pressure, three full 
service applications may be made without recharging 
the auxiliary reservoir, and there would still remain as 
much pressure in the auxiliary as is used with the ordi- 
narv brake. 



INDEX. 



A 

Accelerator Valve 290-294 

" " Arrangement cf Piping in 291 

" Brake Pipe Pressure in 291 

Defects of 293 

List of Parts of 290 

" " Operation of 291 

" " Purpose of 200 

Air Brake. Definition of 330 

" " Freight Trains. All 357 

Part 357 

" " and Signal System (Westinghouse) 1-244 

" Brakes, Inspect 347 

" Cars, Number of, in Train 342 

" Course of 304 

" Gauge Connections 50 

" " Indications 335 

" " Observing the 342 

Testing the 342 

" Piston Packing Rings. Leaky 18 

" Pump Governor. Single 30-32 

" " Operation of 31 

Style "C" 260-262 

'• Operation of 261 

Signal Connections ( ET Equipment) 178 

" Line. Overcharging 109 

" " " Pressure, Testing 110 

" Valves (Duplex Air Pump) 246 

(Westinghouse Air Pumps) Defective 16 

Whistle, Adjusting the 110 

Alternating Engine and Train Brakes 356 

Applications. Number of 360 

Automatic Application 351 

Brake, Cutting Out, on the Engine < B-3 Equipment) 269 

Brake. Use of 146 

Oil Cup ( Duplex Pump) 252-254 

" " " Operation of 252 

Operation I No. 6 Distributing Valve I 186-197 

" " li " "• Charging in 186 

" " " " " Emergency in 104 

Lap In . . 196 



366 INDEX. 

Automatic Operation (No. 6 Distributing Valve), High Speed Service 

in 195 

" " " " Release • 193 

Releasing in 197 

" " " " Service Application 

in 186 

" " " Service Lap in 191 

Slack Adjuster 116-120 

" '• Improper Adjustment of 119 

" " Operation of 118 

Purpose of 120 



B 



Brake Pipe Pressure 

" Valve Handles, Position of (ET Equipment) 

" Valve Handles, Positions of 

Brakes, Failure of, to Release and Causes for Brakes Dragging 

How to release, that are Sticking 

" Leaving, Set 

Braking Power 

" Loss of 

B-6 Feed Valve. .' 224 

Adjustment of 

Distinguishing Feature of 

List of Parts of 

Main Reservoir Pressure in 

Regulating Parts of 

" Valve of 

B-3 Brake Valve 270 

" Automatic Release and Straight Air Application Posi- 
tion of 

Course of Main Reservoir and Brake Pipe Air in . . . . 

Defects of 

Emergency Application of 

Lap Position of 

List of Parts of 270 

Pipe Connections in 

Running and Straight Air Release Position of 

Service Application of 

Slide Valve of 

Locomotive Brake Equipment (New York) 266 

" " Improvement in the 

" Manipulation of 

" " " Piping Diagrams of 

Terminal Tests of the New York B-i 

B-3 Brake Equipment 298- 

" " Accelerator Valve Test of. ..... ... 

" " " B-2 Engineers' Brake Valve Test of 

B-3 

High Speed Controller Valve Test of. 
" " Pressure Controller Test of . . . . 



331 

171 
171 
349 
350 

149 
336 
356 
22!) 
228 
227 
221 
227 
226 
227 
282 

277 
276 
281 
281 
278 
271 
275 
278 
279 
275 
300 
268 
268 
268 

302 
301 
300 
299 
302 
iOO 



INDEX. 



367 



Car Discharge Valve 108 

" Operation of . . 100 

Combined Automatic and Straight Air Brakes, Advantages of 143-146 

Locomotive Brake Equip- 
ment 128-151 

" Locomotive Brake Equipment, 

General Arrangement of 128 

Freight Car Cylinder and Auxiliary Reservoir 113-116 

Defects of . ...115 
List of Parts 
and Their 
Purposes ... 113 
" • " " " " Sizes of Brake 

Cylinders in. 115 
" " " Sizes of Reser- 

voirs in .... 115 

C-6 Reducing Valve 228 

Cut-out Cock, Use of (B3 Equipment) 288 



Dangerous Localities, Approaching 362 

"Dead Engine" Feature 233-234 

" " " Operation of 233 

Defective Air Valves 16 

Triple or Obstructions in Brake Tipe 343 

Triples, Detecting 346 

" " Locating 347 

Defects of the Compressor 28 

D-K Brake Valve 40-47 

Defects of 46 

Distinguishing Leaks in 47 

Emergency Application Position of 44 

Gauge Indications of 47 

Lap Position of 44 

Positions of 41 

Pressures in 45 

Release Position of 41 

Running Position of 42 

Service Application Position of 44 

Descending Grades, Recharging When 355 

Reducing Speed When Approaching 354 

Distributing Valve, No. 6 1S3-207 

" Automatic Operation of 186 

" Charging of 186 

" Connections 178 

" Defects of 204 

" Independent Brake Operation of 197 

Independent Release of 200 

" List of Parts of 183 

" Main Reservoir Pressures in 186 



368 INDEX. 



Distributing Valve No. 6, Removing the Parts of 202 

" " Tracing of Ports and Connections in 184 

" " " Broken Graduating Spring 207 

Divided Reservoir (B-3 Equipment 3) 283 

Double Check Valve (New York) 288 

No. 2 138 

Position of 139 

" " Release Position of 139 

Heading (B-3 Equipment) 269 

" Pressure Control or Schedule "U" 154-155 

" " " " " " Operation of 154 

Driver and Tender Brakes 336 

Drivers Sliding 150 

. 359 

Duplex Air Gauge 37-39 

" " " Description and Operation of 37 

Testing the 39 

" Pump (New York) 245-259 

Cylinders of 246 

Defects of 255 

" " " Inspection of 255 

" '• " Lubrication of 252 

Operation of 247 

Speed of 254 

Starting the 254 

" " " Valve Gear of 245 

" Main Reservoir Control 152-154 

" " " " Operation of 152 

Pump Governors (New York) 262-265 

" " " Adjustment of 262 

" " Defects of 264 

" " " With Siamese Fittings (Westinghouse) ... .32-36 

Cleaning 32 

Cut Out 35 

Defects of 36 

Inoperative 35 



Eight-Inch Air Pump 3-6 

" " " Leakages and Blows in 19 

" " " Operation of 3 

" " Purpose of Operating Parts 5 

" and Nine and One-Half-Inch Pumps, Defects of . 14 

" " One-Half-Inch Cross-Compound Air Compressor 20-27 

Defects of . . 28 
" " " " M " " Operation- 

Steam and 
Air Ends.22-26 

Emergency Applications 339 

Not to be Made When Testing 346 

Empty Cars Ahead and Loads on the Rear of Train 358 



INDEX. 369 



Engine Brake Cylinder Pressure (ET Equipment; 173 

" Brakes Failing to Release 149 

" " Releasing (ET Equipment) 172 

" and Train Brakes, Alternating (ET Equipment) 172 

" " " " Summary of Air Brake Opera- 
tion 318-350 

" Reversing .",.">!) 

Equalizing Piston Packing Rings GO 

" Reservoir 47-40 

" and Its Connecting Parts, Defects of 49 

" " Purpose of 48 

" " Time Consumed for Preliminary Exhaust With ... 49 

ET Locomotive Brake Equipment, No. 6 170-224 

" " " " " Arrangement of 176 

" " " " " Manipulation of 171 

" " " " " Names of Piping of 175 

" Parts of the 174 

" " " " " Principles of Operation of. .. .ISO 
" " " " " Pump Failure When Double- 
Heading With 234 

" " " " " Terminal Tests of the 235-244 

" " " " " Air Gauge Tests of the 235 

" " " " " Automatic Brake Valve Test 

of the 238 

" " " " " Brake Pipe Leakage Test of 

the 236 

44 ' 4 " " " Brake Cylinder Leakage 243 

44 " " " " Distributing Valve Test of 240 

44 " " " " Feed Valve Test of 236 

44 *' " " " Governor Test of 237 

44 " " " " Independent Brake Test of. ..239 

44 " 44 " " Safety Valve Test of 24:; 

44 " " '• " Signal W T histle Test of 244 

Excess Pressure 331 

" " Loss of :;48 

44 " Purpose of 332 

F 
Final Stops — Passenger Trains 362 

G 

General Information Relating to Air Brake Practice 335-363 

Grade Bleed Cocks 140 

" Closing 149 

G-6 Engineers' Brake Valve 50-60 

" Defects of .17 

" " " " Distinguishing Leaks in 58 

44 " •' " Emergency Application Position of 56 

44 " " " Excess Pressure of 50 

44 " " " Air Gauge Connections 50 

" " " " Lap Position of 54 

" " '• " Regulation of Pressures of 57 



37o 



INDEX. 



G-6 Engineers' Brake Valve, Release Position of . 51 

" " " Running Position of 52 

" " " " Service Application Position of 54 

" " " " Standard Pressures of 51 

H 

Hand Brakes, Use of 356 

High and Low Pressure Retaining Valve 123-126 

" " " " Operation of 124 

" " " " " " Positions of Handles on 125 

High Speed Brake ( Westinghouse) 156-165 

" " " General Information Relating to. . . 164 

Compensating Valve, Style "A" (New York) .. .319-324 

" " " Adjustment of 324 

" " ; ' " " " " Advantages of High 

Pressure in 323 

" " '■ " " " " Attaching Spring 

Box on 322 

" " " Emergency of 320 

" " " List of Parts of . . . 320 

" " " Operation of 321 

" " " Packing Rings in . . 322 

" " " Piping in 320 

" " Use of, on Different 
Sizes of Cylin- 
ders 323 

Reducing Valve 159 164 

" " Cars not Equipped With 163 

" Cylinder Pressure of ,. . . .163 

Defects of 164 

" " Emergency Application of 161 

" " Inspection of 163 

" " Operation of 159 

, " " Service Application of 160 

Controller 295-297 

List of Operative Parts of 295-296 

Pressure in Service Application, Advantages of 164 

H-6 Automatic Brake Valve 210-218 

" " " " Charging and Release Position of . . 213 

" " " " Emergency Position of .217 

" " " " Holding Position of 216 

" " " " Lap Position of 216 

'• List of Parts of 211 

li " " " Lubrication of 217 

" Ports of 213 

" " " " Preventing Leakage in 217 

" " " " Release Position of 216 

" " " " Removing the Parts of. ... . 217 

" " " " Running Position of .214 

" " " " Service Position of ' 215 

' " " Views of 210 

" " " " Holding Standing Trains on Grades 148 



INDEX. 371 



1 

Independent Brake Operation 197-202 

" Brake (ET Equipment t 17:; 

" Release 184 

L 

Leakage Grooves 337 

" " Forcing Pistons Past 337 

Leaky Air Piston Packing Rings 18 

Leaks. Testing for 341 

Lever Safety Valve 297-208 

List of Operative Parts of 298 

Loads Ahead and Empties on the Rear 358 

Long Trains, Handling 172 

Loose Reversing Plate, How to Tighten a 18 

Low Speeds, Releasing at 147 

M 

Main Reservoir 28 

" Capacity of 29 

Connections (ET Equipment ) 170 

" " Leakage 29 

Minimum Reductions 355 

N 

New York Air Brake and Signal System 245-329 

" " " Pump Governors 260-265 

" " "• Operation of 248 

Train Air Signal System 325-329 

li Defects of 328 

Nine and One-Half-Inch or Eleven-Inch Pump, Leakages and Blows in. . 19 

" " " " " Pump 6-14 

" " " " " Construction of 6 

" Defects of 14 

" " " " " Diagrammatic Views of 11-13 

" " " " " " Lubrication of 12 

" • Operation of 8-10 

'• Starting the 12 

" Speed of the 12 



Old Style Feed Valve 60-62 

' Defects of 62 

Overcharging : >48 

Signal Line 100 

Over-Reduction 338 



Piston Travel • 147 

(Summary of Brake Operation) 336 

Pistons, Position of (Duplex Pump) 246 



372 



INDEX. 



Plain Triple Valve 68-74 

Cut-Out Cocks in 73 

Defects of 74 

'• " Emergency Application of ........ „ 72 

Release of 73 

Service Application of 70 

Preliminary Exhaust. Time Consumed for 4D 

Pressure Controller (B3 Equipment) 284-290 

Cutting Out the 288 

Defects of 289 

" " Operation of 286 

" " Regulating Parts of 287 

Size of, to Straight Air Brake 288 

Controllers, Styles of 284 

" Retaining Valves „ 121-127 

" Defects of 126 

Pressures. Beginning and Ending of 333 

" Equalization of 335 

Storage of 332 

Pump, Failure of. to Restart Promptly 18 

" Heating of '. 19 

Pump Pounding- 20 

Speed of . 12 

" " " While Descending Grades 349 

Purposes of Triple Piston, Slide and Graduating Valve 82 



Quick Action Cylinder Cap (ET Equipment) 202 

Triple Valves (New York) 303-318 

" Auxiliary Pressure in 311 

" Brake Cylinder Pressure in 310 

" Course of Air in 304 

" Defects of 315 

" Emergency Application of 308 

" List of Parts of. 303 

Operative Parts of 304 

Partial Service Application of 310 

Ports and Passages in 304 

" Releasing 310 

Service Application of 306 

Vent Valve in 312 

Style "S" Passenger 312-315 

" Different Types of.... 315 

Friction of 314 

Graduating Valve and 

Ports of. ... 314 

List of Parts of 312 

" ( Westinghouse) 74-104 

" Charging of .• 75 

Defects of 83 

" Distinguishing Leaks in 83 



INDEX. 



373 



Quick Action Triple Valves, Westinghouse Emergency Application of.. 78 

List of Parts of 74-75 

Release of 82 

" Service Application of 76 

Type "K" 85-104 

" " " Advantages of, in Quick Service 

Application 06 

" " " Cavities in 01 

" " " Emergency Position of 103 

" " " Full Release and Charging Posi- 
tion of 01 

" " " Full Service Position of 07 

" Lap Position of 08 

" List of Parts of 88 

" " " Openings in 00 

" Ports in 90 

" " " Position of Ports in 89 

" " Quick Service of 86 

" " " " Application of. . . 94 

" " " Recharging 87 

" " " Release Feature of 87 

" " " Retarded Release and Charging 

Position of 100 

" " " Retarding Device of 00 

" " " Sizes of ' ■ ■ 88 

Release Valve ( B8 Equipment) 204-29.1 

List of Parts 295 



Reducing Valve Pipe Bracket 133 

Reduction, Amount of 338 

Reductions and Applications 837 

Releasing 540 

Before Uncoupling 347 

Sufficient Time for 341 

Reversing Cock 165 

" Adjustment of 168 

" " Operation of 167 

Rotary Valve Leaking 58 

Running Test 345 



Safety Valve. E-6 207- 

" " Adjustment of 

" " " List of Parts of 

" " " Operation of 

Type "E" 140 

" " " " Adjustments of 

" " " Operation of 

Sander, Use of 

Service Applications 

With High Speed Pressure ... 889 ami 



200 
209 
207 
207 

14:; 

142 
140 
800 
339 
862 



374 INDEX. 



SF Type Pump Governor 229-232 

Adjustment of ... . 232 

Construction and Operation of 230 

Signal Reducing Valve (New York) 325-326 

" 'List of Operative Parts of 325 

'' " Operation of 326 

" (Westinghouse) 105-107 

" " " Adjustment of „ . . 107 

" Operation of 107 

'• Valve (New York) 326-327 

" " Operation of 326 

" " (Westinghouse) 107 

Operation of 108 

Slack Adjustment 336 

Slide Valve Feed Valve 63-67 

" Defects of 66 

Sources of Air to Brake Cylinders With Different Types of Triple 

Valves 335 

S-6 Independent Brake Valve 218-224 

" Lap Position of 223 

" List of Parts of 218 

" Oil Plug of 224 

" " Ports and Grooves of 218 

" " " Quick Application Position of. 221 

" " " " Release Position of 223 

" " " " Return Spring, Purpose of 223 

" " " Running Position of .221 

" " " Slow Application Position of 221 

Standard Pressure Retaining Valve 121-123 

" Advantages of 123 

" " " " Operation of 121 

Pressures for High Speed Service 163 

Standing Trains on Grades, Holding of 148 

Straight Air and Automatic Brake Valves, Positions of 146 

" Brake, Cutting Out the (B3 Equipment) 269 

Defects of 150 

Valve 134-138 

" " " " Operation of 134 

" Parts and Their Uses 134 

" Brakes, Power of . 146 

" Controller (B3 Equipment) 270 

" Holding or Stopping Trains With 147 

" Use of, During Automatic Application 146 

Summary of Air Brake Operation and Train Handling 330-363 

Supplementary Reservoir (B3 Equipment) 282-284 

Switching 353 



Tail Hose, Use of 352 

Terminal Tests — Freight and Passenger Trains 343-345 

Testing Signal Lines 110 



INDEX. 



375 



Three-way and Four-way Cock Connections (Bo Equipment) 287 

Time Consumed in Charging 335 

Train Brakes. Recharging 148 

" " Releasing, Before Detaching Locomotive (ET Equipment). 173 

" " Improvements Over the Old 86 

Two-Mile Test :J51 

Two or More Engines Coupled 353 

" •• '• '• in a Train 202 



W 

Westinghouse Air Brake and Signal System 1-244 

" " Pump Governors 30-3G 

" " Pumps 3-iiS 

" Signal System 105-112 

" " " '• Defects in 110 

Brake Valves 40-60 

" " " Difference in Types of 57 

Triple Valves G8-104 

New Types of 84-104 

Wheels Sliding 337 



^39 1909 



